Running plates, it would seem nothing would be moving much at all. Especially with a mid plate. A pretty well respected tranny guy told me no poly trans mounts. They can break tailshaft housings when used with stock mounts. Motor moves, stiff trans mount doesn’t. That being said, I have run a poly one since I finished the car in 2009. Figure if it was going to break the housing it would have already. I’m was also the designated guy to carry a spare 727 tailshaft housing in case anyone in the group has an emergency! They’re going to have to find some other schmuck to hump it around now that I’m running a 904!!! :):):)