I'm not saying that the t56 can't be made to fit one of our trucks. It probably would not be to difficult in a truck that is using bucket seats. However it is not a popular swap in trucks using a bench seat because as noted the shifter location is way further back than the stock 4 speeds. I believe the shifter is about 18 and 1/2 inches further back. For prewar trucks the gas tank would also have to be relocated as the shifter would be coming up in the middle of the tank. But for most AD and Task Force trucks (47-54 and 55-59) the major hurdle would be repacing the bench seat with suitable buckets. The T56 was also used in Camaros, so you may be able to grab a chevy bent motor, bellhousing, and transmission, and adapt it to your streetrod.
I am not a big fan of the T5 as I don't believe it is strong enough for a hot rodded truck, but it is a fairly ez swap in a stock 6 cylinder truck and seems to match up well to the power curve of a 235. If you are going BIG with your truck you should find a transmission to match. The camaro T56 should do pretty well with up to about 350 HP and 350 lbs of torque.
I wouldn't build a 700 HP motor and expect one of those transmissions to live to long behind it.
John
