350 to 360-doable?

I'm guessing the big problem will be the same one that caused Chrysler to cancel the Sunbeam Tiger when Chrysler bought Rootes Group — the small block Mopar has the distributor at the back of the block. In the Sunbeam, the back of the small block Ford engine is tucked under the cowl — the distributor would have under the cowl at the base of the windshield, completely inaccessible if it had fit at all. Looking at the Jaguar setup, would the distributor be accessible? It's possible it would, since the original Jaguar V12 was a very tall and long engine. But it's one thing to look at.

As far as motor mounts, most swaps go the other way, so I suspect you're on your own. But I assume somebody had to fab the Chevy mounts for the Jaguar in the first place.