I'm not 100% sure, but I do believe the control units are the same.
The pump has a different mounting arrangement.
If you need new rear air shocks I highly recommend that you buy new as opposed to buying junk yard used as they are not that expensive if you buy the Monroe substitutes.
The P/N's for those are on this site.
Just do a search for rear shocks and/or look in the part number listing also on this site.
Here is the link for "Rear Shocks" http://rivperformance.editboard.com/Supercharged-3800-Tech-c2/Suspension-Handling-f6/Write-Up-Rear-Shocks-p15036.htm#15036
If you should need parts other than the shocks, the junk yard can do a cross reference on the P/N's for you.
If you need good used Riviera parts, a lot of us use Ed Morad out of Ohio. His operation is very good and the people are very helpful. They get Riv's in from time to time and dismantle.
Go to www.moradpartscompany.com or you can call them at 216-798-6902 He has an inventory of some Riv parts and they are not always listed on the web site, so if you don't see it on-line try calling them. Good Luck
BTW, Welcome to the board and don't hesitate to ask questions and search this site for a lot of very good and valuable info.