In my travels recently I found these....check them out, as they list as they will work....They list the 89-90 sedan and coupes separately. hhmmmmm....
Bilstein Heavy Duty Shock/Strut - Rear :: Shock/Strut :: Suspension :: Import Replacement Parts
Bilstein Heavy Duty Shock/Strut - Rear :: Shock/Strut :: Suspension :: Import Replacement Parts
These both look the same, so you might need to talk to a live person to clarify, but it's promising. Let us know if it pans out.