If you use the motor mounts that bolt to the front of the block, it's usually necessary to notch the brackets to clear the 350 balancer. That's about a 10-minute operation with a Sawzall or a torch, however, and it doesn't compromise the strength of the mounts.
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!