I have 52 F1, put 1970 style all drum master cylinder on and cant find the right fittings to "T" in the mechanical brake switch. I was going to just weld a couple of brackets under pedal and mount a push/plunger type switch off of the pedal, but just thought I would see if anyone else has ran into this problem first.

 

The threads on the hydraulic brake light switches are 1/8" pipe thread. The correct tee fitting that you need would be a 3/16" inverted flare x 1/8" NPT x 3/16" inverted flare. They are a fairly common fitting. Here's one:

3/16" Brake Line Tee 4 Hydraulic Brake Switch Painless: eBay Motors (item 300331590624 end time Aug-13-10 09:48:12 PDT)

 

You can pick them up at NAPA for around $5.00
brian...

 

i used a lever type switch on mine '54. just get the normally closed one and run the arm under the pedal (between pedal arm and body). when the switch is in the circuit is closed.

 

Just went through this myself. A hydralic brake switch attaches to the brake line and senses the pressure. Blueovalrage has it right as far as the adapters. However hydralic brake switches fail after a few years because the current archs across the contacts leaving corrosion which stop the current from flowing. A mechanical brake switch is the way to go. There a number of them on the market a previous post in this thread. The one I used is from watson's street rod parts in Borza, Connecticut. Just google the name. I checked into other similiar products, but ths one is all stainless steel and has self cleaning contacts. It's $22.00. The hydralic ones are cheaper but a big hassel to change when it fails, and it will!! Hope this helps.