I purchased a 454/425 that I think was used with a TRS setup, anyway the Flywheel teeth are to the outside of the flywheel instead of inside (toward the block). My question is can I use my flywheel from my 454 Mag or will I have a balancing issue? Not really sure what to do here, any comment appreciated. Thank you

Just use a std manual trans ext balanced 168 tooth flywheel

Is the flywheel machined on both side for the ring gear? If so just put a ring gear on what you have. Or move the one from the rear to the front.

If they are both the same generation engines, there's no problem interchanging them. If not, any competent machine shop can machine your existing wheel so that the ring gear will press onto the opposite side... I've done it many times.

Thanks for the replys! I'm not sure if they are the same generation or not. Orginal Motor was a 1993 454 Mag and the one I'm having the issues with is a 1990-93 454/425hp. Sorry not much help on my end. As for if it is machined already or not, I'm not positive. I installed the motor without checking this first, my fault, so I will have to pull the motor to check this out.

It's not often that the flywheel is machined for the ring gear in both positions.

If the engines both have the same rear seal (one or two piece) then they are interchangeable.

As mentioned, just have a machine shop machine down the front side of the flywheel to accept the gear. Anyone with a lathe with at least a 14" swing can do it. Knock off the existing gear with a brass punch. When you are ready to put it back on, heat the gear up with a torch and it will drop right on the colder flywheel. Good luck.
Eddie

Thanks for all the replys! I pulled the engine back out and the flywheel was machined to handle either side for the ring gear. Just pressed it off and reinstalled. Thanks again