What engine was in it originally? The 350 is the same dimensionally as the V-8's available in 65, so there should be factory-original mounts, and frame brackets available. Are you using the original transmission, or upgrading to a later model? Sometimes it's necessary to install a different rear crossmember/mount assembly if you're going to use a later model transmission, but the front mounts should work OK with original-equipment items. I believe by 65, the front motor mounts were on the sides of the engine, unlike the former horseshoe-shaped front mount which required side mounts on the bellhousing.
Jerry
