Why would a shop say you would need a new flywheel

[winfred]

6 cylinder flywheel won't work on a v8, if you want a non twin mass you gotta buy a expensive aftermarket unit

. . . when it went at 116k.

I don't know of anyone with a 540 who has done this swap. Will the E28 flywheel work in the V8s, and can it handle the torque of the 540 without trouble?