I swapped my tranny out for this problem. There is a check valve change and also pressure plate change. At some point I posted the serial number break down for those trannys. Basically a late production 97 is the best choice. I contacted cruiserparts.net and was able to confirm that the tranny he had had the changes by using the serial numbers.
I'm leaving for a week of work annd if this thread is still active I'll try and post TSBs if I can find them
here is the link to the tranny serial number break down
TSB