The 61 still had the horseshoe-shaped mount at the front of the engine, and mounts on the bellhousing, with the transmission unsupported. Later models used side mounts, and a rear crossmember supporting the rear of the trans. The 3-point mount with the crossmember is better, so why not upgrade as you install. It will take a little fabricating, but you'll have a better system when you're finished. BTW, that V-8 bellhousing with the side mounts is pretty scarce now, I'll bet!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!