Welcome to the Org. i may be wrong but i dont believe the 4R100 came with a triple disk TQ.... i would spend the bulk of your mod money on a really beefed up tranny esp if your gonna tow so much.... prob in the range of 4k....now for your 7.3L i would recomend the Edge Evo if you want a programmer or a Dp tuner if you want a chip... the Edge Evo 2 would come with a set of digital gauges so you kill 2 birds with 1 stone... oh and our stock tranny gauge blows... mine will always still on normal where my autometer will literately bee anywhere from 120-220 with the stocker not moving at all....
-Raul