Trans Mount Experts

All the '62-'72 A-bodies use almost the same trans mount, regardless of engine or transmission. I say "almost the same" because the mounts thru 1965 had two threaded studs protruding down thru the bottom of the crossmember, while the '66-up mounts had only one. Other than that, they're identical. You can use a single-stud mount on a '65 or earlier car with no problem, and I suppose if you really wanted to you could drill the second hole in a '66-'72 crossmember and use a double-stud mount in it. There's really no need of the second stud. This is a vertical-shear type mount; the replacements you're finding appear "too tall" because they're not sagged like your old mount. If you take a look at the rubber on your old mount, right close to the central steel plate set vertically into the rubber block, you can usually see the sag lines in the rubber.

Stock replacements are still easily found, or you can get good polyurethane ones from www.polybushings.com , among other sources. Putting in an unsagged transmission mount will do good things for engine and driveshaft alignment.