I ordered a service manual and a set of capstan belts. Problem solved! My tape deck works fine now. The total time to disassemble, replace the worn belt on the "A" deck and put it all back together was approximately one and a half hours. Total cost of the manual and belts was $28.12 (US dollars).
If you order a downloadable service manual, it's a PDF file, so you will need Adobe. Also, you may not be able to easily print all the pages of the manual; the assembly and electrical diagrams are odd sizes and don't compress to your standard 8-1/2 by 11 sheet of paper.
Lastly, when disassembling the motor, you will have to disengage/remove two belts, the capstan belt and the FR belt. When replacing the belts they must be fed around several pegs called "claws." The capstan belt has three claws; the FR belt has two claws. Confirm that the belts are not twisted! You must make sure the reel motor gears are in correct position; you can't put the motor together if the gears are in the incorrect position. After the motor is reassembled, remove the belts from the claws. The belts will slide appropriately into position over the drive gears. The hard part of the job is now done.
Once the tape deck is completely put back back together, plug it in, and turn on the power. The tape deck will automatically reset itself. Test the tape operation buttons to make sure the unit works properly.
Good luck!
Delmar Cologne Reese, June 2007