I called Imperial Services last week and their answer on the polyurethane safety-lock mounts for '62-'66 slant-6 A-bodies (all the same left and all the same right) was "a couple of weeks from now" again
I'm sure they'll be out eventually, but even I — knowing firsthand how product development can drag out for ages — am getting itchy for a set of those mounts!The only mounts left in general stock are 3rd-world items made of poor-quality materials, but they're better than nothing, at least temporarily.
Interesting that Damper Doctors rebuild mounts, didn't know that.
The situation is better for the '67-'72 A-body slant-6s; the 3rd-world types are out there but you can also get a very good polyurethane left-side mount from polybushings.com . You're on your own for the right-side mount for now, but one good mount (especially on the oily side, the left) with one 3rd-worlder is better than a pair of 3rd-worlders.
The '62-'72 rear (transmission) mounts are all alike with one minor exception: Through '65 they have two bottom studs into the crossmember, '66-up they have only one. You can use the 1-stud mount in any '62-'72 A-body, but the 2-stud mount only fits crossmembers with two drilled holes. You can get nice polyurethane versions of both types (with immediate availability) at Imperial Services.
The other alternative to 3rd-world mounts is buying 1st-world New Old Replacement Stock mounts from one of the many vendors of such parts. Old Car Parts Northwest has a fair stash of the '62-'66 mounts, the '67-'72 mounts, the rear mounts, and a couple months ago when I was there I counted at least half a dozen of the extremely robust '60-'61 Valiant/Lancer "vertical shear" type mounts, which seem never to wear out. The left vertical shear mount would require welding a tab w/bolt hole to the mount "foot" or to the K-frame if you wanted to use it in a '62-'66 car, but it'd still be a relatively easy and "right now" way to have a sturdier engine mount in a built-up '62-'66 application.
(And since I brought up Polybushings, I did call Johnny over there last week, as well — he's working on our polyurethane spools for the '73+ mounts, and seemed in principle interested in working on some kind of extra-rugged mounts for the '62-'72 cars, either a spool-mount retrofit or a vertical-shear arrangement, perhaps. We both agreed it's best to get the '73+ spools done first, though!)
simple task really