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Can I get some tips on how to remove the dashlights dimmer switch on my '39 Six? The knob pulls off from the outside and one is left with a chrome or stainless bezel or escutcheon, if you will. I tried, but could not get it to budge. Are the two notches on either side of the stem supposed to be used to unthread the thing?? Also, I'm not sure what the deal is with my switch re the wiring. It looks like there are 3 contacts on it, but one of them is at the end of the travel path of the switch and may just act to shut the lights off if it is turned all the way. The other 2 look like proper wire-lead connections, but I only have a wire to one lead. My thinking is that while I have the speedometer out and have reasonable access to the switch, I'd like to remove it, test it and reinstall it, wiring it properly. At his point I can't even seem to get a screwdriver on the contact tabs to loosen them, thus the desire to remove the switch.

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Looking at the schematic the power in from the headlight switch tail light terminal will be one of the switch terminals which also has a wire going on to the tail lights. One of the other terminals will be turned on for the reading light and the other terminal will be coming from the rheostat portion for the instrument lights.

I believe this is the tool that is needed to remove the switch. Note the two small prongs on the end which will fit in the depressions in the bezel. You might be abe to use a modern smaller size adjustable spanner wrench by filing or grinding the round pins to fit the depressions. The spanner wrench is available from Amazon and other parts stores or there is a similar tool used for some later wiper switch bezels that is just a flat piece of steel with the center and edges ground or filed out to provide clearance for the knob shaft and leave a small amount to fit in the depressions. A pair of pliers or a crescent wrench could be used to turn the steel.

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Thank you Howard. At this point, I am mainly concerned with getting the switch out. Based on the diagram of the Packard tool, I'll try and make something to fit into the slots. I THOUGHT that looked like how it should come apart, but before I wrecked something, figured I'd better check first. Once I have it out, I will TRY and understand the wiring requirements but definitely not my strong suit. Hard to figure where the wires that should be there, went - maybe the switch failed and somebody bypassed the thing to at least have lights, albeit only at the full brightness setting. Maybe I should just leave well enough alone, but I love having little things like that, work. I'll report my results once I get it out. Thanks again for your help. Chris.

Chris, as pointed out, the bezel is a decorative nut and using the special tool is the best way to remove it without damage, especially if it's very tight. The round spanner will work too but one with the flat blades is far better.

Can't tell without measurements or trying it, but it appears that just an ordinary Standard Ignition wrench DT-5 might work. This is the tool designed for electrical connectors on, among other things, Northeast distributor caps. These are often seen at flea markets, not uncommon as far as I know.

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Wow, thanks for that Dave, big help! The DT-5 picture you posted sure looks like Howard's 1st pic and if I could find one, that would be 'Dolly's pleasure', if you know what I mean?? Notwithstanding, I think I could make something out of say a piece of 3/8" galv. pipe and cut it from both sides until just those little tabs were left and then saw down from the end. Might work... I'll start with an internet search of the DT-5. Chris.

Okay, so the internet did not yield much when I queried 'DT-5 Ignition Switch Wrench' or any variation/combination thereof. I looked in the junk drawers and came up with the center screw.bezel for a light fixture and cut it down, leaving the tabs for the dimmer switch escutcheon. (See pics) It worked perfectly and the dimmer assembly came right out. Now I need to figure out a) how to test the switch to see if it works and find a replacement it if it doesn't, and b) how to wire the darn thing so I can have dimming lights. My GUESS is that the switch quit working and somebody 'before me' bypassed it so as just to have dashlights, at full brightness. If this was the case, could anybody tell where to look to find that bypass, so I can hook it back up?? I am a little challenged when it comes to wiring, but I will persevere here until I figure it out, so please keep it 'basic' with any explanations so I can get them through my thick skull! Many thanks to any and all who respond. (and have responded) Chris

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Good job, Chris! It looks very professional and almost "period" for your car.

Good job on the tool.

I can't see what is happening behind the wiper but I suspect there may be an end of the rheostat wire connecting to the top right terminal. If there is then see if this might be the way it hooks up.

If no obvious wire connection to the terminal, if you can take another photo with the wiper in a midpoint position and one of the front side that shows the rivets and anything they might be attached to then we can figure it out.

From what I see I suspect there could be a corrosion build up in the switch. Later year dash rheostats which were mounted on the headlight switches had a fixed and movable plate which rubs against each other to make the connection. In your switch the fixed plate looks to be the thick metal under the wiper with a solid leg that appears to be extending to what I call the power in terminal. Corrosion builds up between that fixed plate and the movable contact area below the thin wiper and the increased resistance is enough to prevent the dash lights from illuminating.

Ross has had good results in cleaning later switches by pushing a tiny bit of valve grinding compound under the movable plate and the wiper over the rheostat wire and working the switch to get the plates and contact areas shiny clean. Once clean use some brake cleaner or contact cleaner to get rid of any left over valve grinding compound. Contact cleaner would be best because it leaves a film that kind of hinders corrosion from forming again as quickly. If you use brake cleaner try not to saturate any phenolic or plastic that can be damaged by the cleaner.

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great job on the tool. Switch "looks" good, what typically happens is as stated, corrosion on the "finger" that runs along the embedded coil. I have also seen the phenolic plate become loose from the swedged end of the shaft and need to be peened just a little bit, carefully.