JBL D112 MOD

[Mick B]

 I an very new at this  but an not afraid to let the smoke out if I learn something from it.
I have this JBL D112 subwoofer and the integrated AMP-IC S64AMI is not available and that's what has blown! I would like to replace the output amp with maybe a few 2SC5200/2SA1943 using as much of the existing circuitry as I can, there is nothing wrong with the Pre-Amp or Power Supply and it was recaped about 2 years ago. ANY idea's will be entertained, I have a large supply of components so this will cost almost nothing if it can be done at all. Please note: I have a few schematics of different revisions with what looks like minor component change. I'm only posting one if this grows legs I'll add more pictures and documents. It's a business doing pleasure with you. 
Thanks Mick