You will need new engine mounts.
www.engine-swaps.com for them
You will also need a new trans since the bellhousing cant be taken off an auto to put on a big block bell housing.
Probably will need a new radiator, one form a big block car, so inlet nad outlet are on same side.
If it doesnt have a 8.75 or dana rear end, you will need to get one sooner or later.
Cant think of anything else right now.