Jay, those are both BMW Universal wiring harness radios; most 90 and earlier cars have the proprietary connectors.
BUT!
There are two options:
1) The wiring harness itself is modular and can be replaced with one from a later car (I have a few of them, in various states). It's a bit of labor to pull everything out, though.
2) BMW actually makes and sells a harness converter (that I didn't know about until a few weeks ago) that allows pre-universal harness cars to simply plug in to universal harness radios. I don't remember the part number off the top of my head -- it's in 61 or 64 in ETK. Poke around and I'm sure you'll find it. Last time I looked, BMW warehouses throughout the US had them, so you should be able to order it from a dealer or through me if you choose to go that route.
best, whit