la vs magnum

A 1988 to 1991 LA Block would be a good one to look for (this is what I have).
Since they have roller cams and the 308 heads on them.
Magnum blocks are ok as well, I'm just not a big fan of their stud (err pedestal?) mount rockers on their heads.

Here are some good info for magnum to LA parts interchange.

(I'm sure you were probably aware of most of them)

http://www.magnumswap.com/using-la-parts-on-a-magnum

*Edit* Correction: 1985-1991 318 (5.2) and 1989-1992 360 (5.9) were roller cam LA blocks.
Mine is a 1991 360 LA block.