I'm not sure if this is original to the car but looking at it's condition and factoring in that it was the first thing to go when I got it up here last year, I'm assuming it is? So, what say you?
Does it have bleeder screws? And is there a 2 digit code stamped in the small machined area at the front?
The parts and illustration manuals are the ones that the Buick dealer would use to look up parts. They come in really handy.
Weirder things have happened. Part of me thinks this might be original to the car, especially considering the previous owner only put 8K miles on it in the 36 years he owned it. I'd have to ask if he could recall replacing it.
I thought all of the original master cylinders had bleeders on the side and the repo's did not? I had my original rebuilt since all of the repros did not have the bleeders. CT was the code for mine I believe but that was for a '68.