I am running the stock type of master cylinder and I also still have the stock style brake cylinder switch still installed. Because it quit working consistently, I just added the new "adjustable arm" style switch I linked to you and simply moved the wires from the stock type switch to the new "adjustable arm" brake pedal switch. That way I did not have to find a plug to replace the stock type of switch at the end of the brake cylinder distribution line block. That's actually the 3rd stock type of switch I used. The first I think might of been original. The 2nd one worked better but after a couple years started acting up intermittently. The 3rd one was a low pressure version. It was supposed to work with less brake pedal pressure. It worked for about 2 years and the it pretty much quit. So I found the adjustable arm style switch. Made a bracket for it to mount on top of the frame rail and it's been working dependably for years now.
So if you go that route, just take the wires off your present brake light switch and connect them to your newly installed adjustable arm style switch. About it being the 6th wire? I don't know. On a '56 stock wiring they are both Green wires. One comes from the A terminal on the headlight switch and the other Green runs to your turn signal switch. When the turn signal lever is in the middle position that Green wire feeds 12 volts from the headlight switch to both rear tail lights brake filaments, through the brake light switch when brakes are applied.

It's hard to find a mechanic who runs a good shop to work on old vehicles around here. There's a resort area not too far from me that has a shop that does that kind of work in addition to the modern car repairs. Word on the street is they are having 2nd thoughts about continuing the Classic part of it as they are getting tired of people complaining about the cost of repairs. Along with the headaches of finding parts, etc. New car, classic car, old work vehicle, some things never change! LOL!

About the Ammeter. I like them too. But pulled out the one the O.P. installed in my truck. The wiring was bad, used #12 household wire, ran through the firewall with no grommets, and I was afraid some day all that current that could potentially flow through one in the event of a fault could cause a fire. I replaced it with a voltmeter which I like better because I know what my battery voltage actually is. And with the key off it's out of the circuit.

 

Hi Marten: Ive got that switch on order. The one that you mentioned. Trying to find
everything I will need to rebuild my brake system. Found several isoated spots where my hard lines were crushed. They are steel and wondering how they got that way even noticed plyer teeth marks in a few places. My master cylinder is full of rust and pits. Could not be leave a new master cylinders cap is plastic. Made in China. I think I am going to try to find a master cylinder made in the USA. Alot and I mean alot of NAPA parts are made in China. I checked with( In Line ) and they did not have the stainless made up for my 1955 F'100. Its on order the material is made in the USA. The wheel cylinders are all made in China. Dang. AJ.

 

Aj,
I haven't done buisness with them (yet) but a guy I know really likes Kanter Auto parts. He says they're stuff is really high quality and he has been very happy with them. If you like you could get a complete brake overhaul kit for you 55:

https://www.kanter.com/i-30560690?q=...3DFORD%20TRUCK

I see they list just the wheel cylinders at $45 each and a master cylinder at $175. I admit that sounds a little high , but if it's good quality it might be worth it. Go to their website do some shopping then give them a call.
. About the Chinese made parts. I wish I could buy only American too. But it seems hard to find or even get decent Chinese parts that USED to be made in America anymore.

 

If cost sensitive, Rock Auto has much of the brake parts you are seeking, including wheel cylinders for under eight bucks: https://www.rockauto.com/en/catalog/...+cylinder,1952

 

My brake switch is similar to the one posted by hooler1. For the brake lines, it is not hard to make up your own. I did that. I borrowed a bender but you can buy them as well. Then get the fittings you need. It is a great learning experience. Don't be afraid to try it. If you don't know someone that has do it before, perhaps try asking on a local facebook or other social media group. You will be amazed how many people with hot rods are willing to help out.

 

Well thanks for the reply what I ended up.doing well last week I ordered the NAPA overhaul kit. RAYBESTOS. Made in China. I got the kit last Monday. Looking at prices and decided to pull my master cylinder just to see what kinda shape it was in. No pits really looked pretty good no corrosion or the usual problems you find. I've cleaned it up. The resorvor was the worst. Lots of particles but the vent holes were clear. I soaked it in Naval Jelly. And cleaned the distribution fitting and bolt. I had an extra fitting bolt that was off my 56 maybe my 54. I owned years ago. It was in alot better shape even the seal washers were copper I heated them bright red. The Naval jelly will be done Sunday. I will take it and soak it in alcohol. And way it's worth a try to rebuild it , It's a Wagner master cylinder. AJ