STOP! Don't make any decisions without a rule book. Read all of it. Then read it again. Then again. Then start asking questions about the 50% of it you didn't understand.

A 1983 BMW 320i is classed in ITB at 2460 with driver.

I'm not a BMW guy - don't have any idea what an M10 is. Is it a 320i, or share key parts with a 320i? You can't use parts from a car that's not on your spec line unless those identical parts were stock on cars on the spec line. Even the 77-79 320i is on a different spec line than the 80-83. Those M10's might be useless for 320i parts.

Not sure what the 2002 comment means. The most recent BMW classed in ITB is a 1986 318i.

Hope this helps. Good luck.