I didn't even think about the jeep motors being too tall. That's something I'll definitely have to check. I guess that's the whole reason for the slant in the first place.
Since I'll have to replace the floorpan entirely anyway, modifying the crossmember and trans tunnel doesn't seem like that much extra work. An 833 OD with with slant six is definitely the simplest, but they seem hard to find and expensive.
Wilcap will make you an adapter for the GM 2004r transmission. They have the program as there was a group buy a while back. They may have some left over.
Do you mean for the /6? That would definitely be something to look into, as I've heard nothing but good things about the 2004r.
The big problem is that I want to stay away from both v8s and adapters, which seems to limit options. The pentastar and T5 swap on the forum looks really awesome and well done, but involves too much fabricating for me. I'd rather have the trans and motor work with just factory parts: no custom machined pilot bushings, etc. So basically I guess I have to choose the best transmission and then pick an engine that would work easily with it. (The only exception I would make would be if I could easily stay with the slant 6.) I thought about a 3.9, but it seems like after figuring out all the ignition and carburetion problems involved in that swap I'd be left with a motor that's slightly worse than a 318 and not much lighter. I love the 318 I just don't really want an engine that is such a tight squeeze on this car. I even considered a volvo motor, since 1990's wagons can be had for a nickel these days.