72 monte works fine, and is the same as chevelle, lemans, and cutlass. The spindles, caliper brackets, backing plates, and rotors are nearly identical to '69 firebird.
Use your drum steering arms. Calipers and steering arms face rear. Just put them on the sides of the car where they will do so. Use monte calipers and hoses too. They should meet the drum lines w/o the major modification needed to use Firebird calipers and hoses.
There are not 3 proportioning valves.
There are 2 valves which regulate pressure, and there is a splitter with warning switch. One valve delays front application, and one restricts rear pressure in proportion to front.
The splitter was the same on disc and drum cars to 1971.
You can use the combo valve from the monte to do all the functions, or you can get a front delay valve and use it with your drum splitter/switch.
If you are front heavy, you will also need a valve to regulate rear pressure. FGF's used them on v8 A/C cars only.
