408 stroker motor mount and transmission mount recomendations
Haters gonna hate.
I've recently gotten mine on the road with a similar engine. I went with the poly-loc mounts from Schumaker but it appears they are out of stock. Several members have told me that they won't hold up to 500 ft lbs anyway. Some members drill a hole through the mount and use a bolt and nut to keep them from coming apart. Others use a torque strap to keep them from tearing.
The only other real choice is solid steel.