You only need FG outdrive cups if you use FG bevel gears. chevyman_de mentioned they (at HobbyThek) put Carson bevel gears into FG alloy housing often if the bevel gears are in good shape. If you bevel gears are hosed (mine were sheared off pretty badly) then get the FG gears and FG drive cups.

One other thing - FG makes a small bevel gear mounting tool FG #8505. It is a cross-bar thing that helps sandwich the gears together for placement into the diff housing. The tool is about $8 USD and will keep you from pulling your hair out trying to get the gears in place.

Also pick up some heavy grease from an auto parts store. I used Lucas 'Red and Tacky' grease. You will want to ensure a good coating of grease on the gear teeth.

This is the limited slip diff assembly instructions. It is close to what you will need to do with the 8484 case.

http://www.fg-modellsport-gmbh.de/_P...N/A.8485-5.pdf