what year truck ?
firewall mounted booster and master or floor mounted ?
all drum, or front disc ?
if floor mounted you will need to run residual valves for front and back.

http://www.ecihotrodbrakes.com/brake_facts.html

http://www.ecihotrodbrakes.com/images/pic03_brakefacts.gif

http://www.ecihotrodbrakes.com/images/pic04_brakefacts.gif

hope this helps...

leonard

1957 Chevy 3100 1/2-Ton
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