Search the site, many discussions (and people who have done it).
The main Axis/Vegas mods 1.2.3 thread has a few people who have done it (although you'll have to go through a bit).
The main two sources seem to be
Rec Pro RV Recliners and
Shop4Seats (I believe Shop4seats is a little bit more expensive than Rec Pro).
We went the Shop4Seats route as I wanted the middle seating position to still be available.
Thor Forums
