I used em' on my 72'Sat 400/727. They worked great,much easier to get at the plugs and route the wires. Mine fit close to the PS box but didn't touch it, I had new motor mounts maybe that made a difference. You have a little bit of adjustment in the motor mount brackets if you want to take the time to adjust everything. Loosen the bolts and jack the motor up then re-tighten the bolts, just adjust every thing BEFORE you get your exhaust system welded up!