Thanks for the info guys, if I ever have that code again I'll consider making a shift kit like in Mike'* write up, but as long as changing the fluid keeps it shifting properly I'm not going to mess with it, I've not seen that code in a few years so hopefully I never see it again.

Well, after Mike helped me figure out what that piece of debris was that I found, I am wondering what is the usual charge to have somebody rebuild the transmission for you, provided they possibly let you provide the parts?
I'd do it myself, but I'm not sure I know enough to tackle the job..

Oh yeah, the plastic I found I now know was part of the 4th clutch thrust washer. :(