Ive heard about this being done, and Im on a low budget of coarse but  how does one do it, is it worth it, and how well do they work? I got an 85xj

i saw this on franks fsj garage.com(or somthing like that)  

Would only work as far as I know if you use an A/C compressor that has it's own lube oil sump. That is does not rely solely on the oil in the refrigerant for lubrication. An old york compressor would probably do the trick if you have the room to mount it.

I don't know if you have figured out how to add OBA if not there is an article on this web site http://www.madxj.com/ it id for an XJ but should work with any 4.0.