I am gearing up to swap a 00 LS1 (WS6) engine and a T56 trans in my 01 Silverado 4.8 / 5 speed. From what it looks like and from talking to Allen if I use my front assessories, oil pan and wiring harness I should have a pretty straight forward swap. It looks like the T56 is about 2 1/2" longer than the NV3500 trans. but I think the trans mount is almost dead on. I think the shifter will be back about 10 - 12". Both of the trans use a hydraulic clutch release but the connections are a little different. I am thinking seriously about installing a new cam since this would be the ideal time, I have been looking at the ZO6 cam, I would like to make as much torque as possible and still be able to turn 6 g. If any one can shed some light on this swap I would appreciate it.