Solid motor mounts?

Solid motor mounts?

I had a friend build me some solid motor mounts for my 340 Swinger back in the early '70s. I never had any objectionable vibration. Of course, the engine was internally balanced by an extremely reputable machine shop.
Oh yeah, and I ran a rubber trans mount for the 727 back then and never experienced any breakage - both street and strip driving with a reverse pattern manual shift trans and 4.89:1 rear gears.
Yeah, it was quick. Wish I still had it.