I will leave finally suggestions to Roadrunner or others, but I would stick with plain MerconIII/Decron ATF until you get it all changed out. That means after several 4 quart drops with oil changes as Roadrunner suggested above. Then after riding around with that good fresh ATF for awhile, then either have your tranny flushed and have the Trick Shift used instead of MerconIII ATF or you could do a "transfusion". For more information on that procedure, just search here in the tranny forum using that word.
I would not suggest mixing two different types of tranny fluid.
I have read of one other here on the boards that uses the B&M Trick Shift and seems to really like it.
