360, LA360, or Magnum 360?

This site isn't done yet, but there's a lot of information about the magnums and putting them in place of an LA here:

www.magnumswap.com

The 89-91 LA style 360 have roller cams (though there are supposedly some leftover non-rollers in there so be sure what you are getting)

The Magnum has a number of other advantages as mentioned here.