trans bellhousing changeout?
 

I found a transmission for my ML, but the bellhousing is cracked at the cooling line threads. Is there anything preventing a regular guy with regular hand tools from swapping the bellhousings of my old and maybe newer trans?

It simply unbolting the belhousing and swapping it out? I suppose I'll need some gaskets or o-rings?

It's not quite as simple as un-bolting the old one and bolting on the new one, but it's not that hard to do either. The B1 clutch assembly and front pump will need to be swapped over. Swapping them over to the new bell housing is no big deal, but getting everything lined up just right can make re-assembly a bit of a juggling act. It might be a good idea to pay a few bucks to someone who's done it before. It doesn't take very long to do. Good luck

My MLs trans started slipping in and out of gear at stoplights. Shifted fine at all other times, and made no unusual noises. So I bought a dipstick, a filter, and MB oil. Dropped the pan. The oil was black, and I found a few very small needle bearings in the pan. I bet my pump is damaged from metal in the oil, on top of whatever the needles came from.

Can I use the bellhousing from my trans, and the pump and clutch from the replacement?

Thanks for your response!

Yes, from your description of the condition of your original transmission, I think this makes sense. Let us know what happens.