EX,
Check with Doug or Bob at ERA to be SURE...but if your early 427 uses Tilton brake cylinders, the following may help...I dunno if they ever used Girlings (probably the same switch) but check.
I just replaced one of the switches on ERA 289 #2027...built about 1998.
Doug at ERA said they now use a "Cole Hersee Co. #8626" brake light switch.
Cole Hersee is not common in So Cal...even at a NAPA type store...so you will probably have to order one. Cost ~$10.50, I got two since they are hard to locate...took about a week to get.
Each master cylinder, (front and rear), has a switch threaded on at the back
of the cylinder... you can use either one...if the other is not leaking/seeping (mine was) just move the lead to the other switch.
IMPORTANT !!!!! the original switch/wiring harness used by ERA on my car, circa 1999, has "push-on" spade connectors...the Cole switch uses screw on terminals...
I made up a wiring adapter...a pair of three inch long pigtails with a "spade " on one end and a "screw on at the other end. Now I can use either type switch.
If you need seal kits for Tilton or Girling stuff try Andy Porterfield in Costa Mesa, So Cal. ( He may have brake light switches also.)
http://www.porterfield-brakes.com/
They were about $22.50
Porterfield has a LARGE inventory of hydraulic parts, has been an active racer in SoCal SCCA and vintage for years.
Given the age of your car and the climate in Hawaii, before you order anything, you may want to pull the cylinders and see if they are rebuildable...they may be too pitted. New cylinders aren't too bad price wise.
While the car is up on stands, consider cleaning and greasing the balance bar assembly...grit gets into the box over time.
Cylinders have to come out either way, whether you rebuild or replace...have fun with the hydraulic line
Hope this helps you anticipate some problems I had.
Pete