power booster/master cylinder help

[tropa]

just got done doing my drum to disc conversion on my 64 c20, now down to brake lines, power booster and master cylinder. I got this booster at the junk yard for $16 bucks at the junk yard off a 1967 c20 that had drum all around. went to auto zone and bought a new master cylinder and they said that this is the one i need if I have disc brakes but the problem is the push rod (if that is what it is called) is too long even if adjusted, looking online, this master cylinder also fits 1973 and above. the original master cylinder was smaller and was deeper where it connected to the rod. would it matter if i buy the original master cylinder with the new disc brakes and return this one in the picture?

thanks in advance.

[protrash64]

I think, not positive, but the ms/cyl for manual brakes may be deeper. I dont know if one would work for what you are doing; just a thought.

What about cutting the rod??

[Captainfab]

I've not seen a booster like that with the long intermediate pushrod. You might try a manual master cylinder for disc brakes, Those typically have the deeper bore in the back of the piston.

[tropa]

Thanks Captainfab and Protrash64, yah best bet is to put the manual master cylinder back on... I swung by O'Rielly's and ask the guys there ... with my luck the guy helping me out ran into the same issue two years ago with his c20 ... checked out his truck in the parking lot and he has the same booster and put the manual master cylinder in with his disc brake conversion and had no issues. he said it might be a mistake on autozone coz it didn't show this master cylinder on their PC for this booster. The other option I have is to get a 73 and above booster, i think i'll return this master cylinder and get the manual one... i'll let you guys know.... thanks again