Hi Joe 50
Looks like you'll need a rebuild,
I just got mine back last week... It was in for a rebuild too. My symptoms were that it was "slipping" between the second and third gear (engine reving-up) and the engine brake was not affected when lever was put in 2nd...
The parts that were replaced are the "high clutch" assembly, the "drum" and the "brake band" I saw the parts but don't ask me what they do. All I Know is that my wallet in $2000 (Can) lighter... But the car drives beatiful now.... In fact, I had this car for a little over 2 years now and it has never performed this well before! I'm in love again
I hope there's a reputable transmission shop in your area that can fix yours.
Good luck!
Joe 90