360 Flexplate?

I am looking at buying a flexplate that is for a 78-92 360. I have a 74 360.

My Mopar Performance book says that all flexplates are basically interchangeable.

But, if I use that flexplate I will need to get a 360 balanced (externally) convertor, correct?

If I want maximum interchangeability, I need to use the B&M and then I can basically run any aftermarket convertor for a 904, right?

I think I know the answers, but I do want to make sure so I don't get in a bad way.

Any advice?

Thank you for your help as always, ROB