Shop car context: all three instruments came out of VIN 108689 in August 2026 and went to Palo Alto Speedometer for concours restoration. The removal below is complete and documented. What comes back from the restorer will be added to this guide when it arrives.

§1 · Before you touch anything

Photograph the dash intact. Not one shot — every angle, close enough to read the relationship between each gauge, its bezel, and the dash face.

You are not documenting the gauges. You are documenting how they sat, because that is the information you will not have later and cannot reconstruct from a parts diagram.

356A dashboard with all three instruments still installed, seen past the steering wheel
The dash before anything came out. Speedometer, tachometer, and the combination oil-temp/fuel gauge, all in place.

§2 · Number every wire — then don’t trust the numbers

This is the step that makes the whole job reversible, and it’s the step people skip because at the moment you’re doing it, the wiring seems obvious.

It will not be obvious in six months.

We numbered every wire with green masking tape before a single connector came loose, and photographed the routing and terminal positions as we went.

Behind the dash: wires individually numbered with green masking tape Detail of numbered wires at the gauge terminals
Every wire tagged before disconnection. This is twenty minutes of work that saves a weekend of continuity testing later.
Where this goes wrong: masking tape adhesive fails. Over months in a garage that swings through temperature and humidity, tags curl, fall off, and go illegible — and restorations measured in months are the normal case, not the exception. Tape is the working label, not the record. Photograph everything, back the photographs off the phone they were taken on, and write the numbering into a text schedule that lives somewhere other than the car. Three copies of the map, in three different failure modes.

§3 · The connectors

Old connectors resist because they’re corroded and because their insulators have gone hard, not because they’re secured by something you haven’t found. Twisting cracks them. A straight, steady pull with needle-nose pliers gets them off.

What it cost us: the porcelain connector housing on the brake warning light cracked before we'd worked out the technique. Every connector after that came off intact. Worth knowing that the learning happens on the first one, so start with a connector you'd least mind damaging — and source a replacement porcelain housing early either way, because they're getting hard to find.

§4 · When the gauge won’t move

This is the part worth reading even if you skip everything else.

The combination oil-temp/fuel gauge would not come out. The rear mounting bracket released easily — which meant, by elimination, that the bracket was never what was holding it.

The front bezel had bonded itself to the dashboard. Fifty years of compressed rubber seal plus accumulated dirt had effectively glued the bezel ring to the dash face from the front, while we were pulling from behind.

The failure mode here is obvious in hindsight and expensive in the moment: you conclude the bracket didn’t fully release, you pull harder, and you tear the dash.

What worked:

  1. Masking tape over the dash around the entire gauge aperture — the dash is what you’re protecting, and it is not replaceable.
  2. Work the perimeter progressively. Not one spot until it gives; around, and around again.
  3. Accept that it takes longer than it should. The bond releases gradually or it takes dash material with it.

The gauge came out with no dashboard damage.

Diagnose before you pull. If a gauge resists after its bracket is off, the resistance is in front of the dash, not behind it. Stop and go around to the front. Every additional pound of rearward force at that point is going into the dash face, not the gauge.

§5 · What to photograph once it’s out

With the gauge on the bench, the rear case is a provenance document.

Ours carries 6V, 27/19, handwritten inspector markings, and date and inspection stamps — consistent with an original VDO instrument. Those marks are in exactly the same evidentiary category as an engine case stamp or a gearbox number, and they are one careless refinishing job away from gone.

Rear gauge case stamped 27/19 with inspector markings Rear gauge case stamped 6V
The rear-case stampings: 27/19 and 6V, with handwritten inspector marks alongside. Photograph these before the gauge leaves your hands.
Rear of the combination gauge showing terminals with numbered tape still attached
Rear of the combination gauge, terminals still carrying their numbers.

§6 · Assess before you decide what to ask for

Disassembling far enough to inspect — chrome bezel, glass, and sealing gasket off — is what turns “restore it” into a specific instruction.

On our combination gauge:

ComponentConditionCall
Dial faceExcellent — silk screening intact, no visible fadingRetain and restore
PointersAppear originalRetain
HousingOriginal finish, untouchedRetain
GlassPitted through and clouded, not merely dirtyReplace
Rubber sealHardened and compressedReplace
Combination oil temperature and fuel tank gauge face Gauge face seen through the pitted original glass
The combination gauge. The speckling across both images is pitting in the glass, not dust on the lens — that's what justified replacement. The dial underneath is in excellent condition, which is what justified keeping it.
The preservation line, drawn explicitly: replacing glass and seals is not a compromise of originality — they are consumables that have failed at their job. Replacing a dial face would be, because the dial is the instrument's identity. Knowing which is which before you call a restorer is the difference between commissioning a result and hoping for one.

§7 · What to ask a restorer for

We chose concours restoration over the lighter repair service, and sent a written request with the gauges rather than a phone conversation. Enclose a copy in the box and email the same text separately so there’s a timestamped record on both sides.

What we asked for, and would ask for again:

  • Return every original part replaced, including the unusable ones. Glass, seals, bezels, internals. They belong with the car’s documentation.
  • Before/after calibration or bench-test data for each instrument.
  • Calibrate to stock specification and confirm 6V operation in writing.
  • Preserve the odometer reading — record it in writing before shipping so you can verify it on return.
  • Retain the original dial faces, and preserve the rear-case stampings and inspector marks.
  • State the fuel sender resistance range the gauge is calibrated against. A perfectly restored gauge reads wrong against a mismatched sender, and the ranges quoted for 356 senders differ meaningfully by type. Measure your sender while it’s out and compare. See the fuel tank guide for the measurement.
  • Contact me before proceeding if anything changes scope, cost, or the ability to retain original material.
Honesty note: the instruments are at the restorer as this publishes. The removal is complete and documented; the restoration outcome isn't ours to report yet. Return-inspection results, calibration data, and the sender range will be added here when the box comes back — including anything that didn't go the way we expected.
Combination gauge wrapped and bagged, ready for shipment
Packed and going out. Insure it for what it costs to replace, which is not what it costs to restore.
Parts used Affiliate links · they fund the research
Green masking tape
For wire numbering. Any low-tack tape works — see §2 on why tape alone isn't enough.
Hardware store
Porcelain connector housing, brake warning light
Ours cracked on removal. Getting scarce — buy a spare when you find one. PN to be confirmed.
Stoddard
Needle-nose pliers
The connectors come off with a straight pull once you stop twisting them.
Hardware store

Where this guide comes from