ZF-5 Slipping?

[EPA Special]

Hey guys, havin some problems with the tranny in my 95, itll do it whether its in gear or out of gear, clutch in or out, it makes this horrible grinding sound. its appropriet to speed so the higher the speed the louder the grinding and does it all the way until stopping. it also will only sometimes go into R. all help is greatly appreciated! Im in the central part of FL about an hour away from Tampa Bay if there are any near by members.

BTW it will only do all of that when im slowing down, as long as im working forward itll go into gear fine and not make any noise. Replaced flywheel, clutch disc, pressure plate, pilot & throw out bearing Last week. never did it before the replacement.