An update on the replacement of the 5th bow motor - I got lucky! after two weeks of not being able to lower the roof I tried it one last time to gain access to the underside of the tonneau, prior to resorting to more drastic measures, and for some reason it worked. This made changeing to motor no problem. The 5th bow motor kit includes new latches, linkage, wiring and the motor; by Saab standards it looks like a lot parts for the price. The latches and linkage did not seem to fit my 97 but there was nothing wrong with my old ones. The total job took less that an hour and the top is now working great again.
I think boxman has the right idea, the best way to access the motor with the top in the up position would probably be to remove the upper latch brackets from the top (inside) and not damage to trunk interior or plastic liner.
Hope yours works out as well
Hank