im swapping trannies, the TH350 in place of my 4l60e. I heard that the 9" tailshaft was the way to go so i wouldt have to lengthen my driveshaft. I ordered the GM parts for teh speedo and the sensor part number 8655314 is way too big to fit in the hole of the tailshaft where the factory mechanical speedo went. are there different 9" tailshafts made...one with a larger and smaller hole, or what? if so, what make/model 9" tailshaft am i looking for? the tranny rebuilder said that he has only seen 6" tailshafts with that big of a hole. thanks for any help

Chad