It isn't all that bad. I have done it before on a friend's truck. I can't remember exact measurements, but I do know that we had to have the drive shafts altered a little bit seems like it was around 2 inches. Also, the crossmember will need to be drilled in a different spot to get the rubber mount for the 4500 to bolt into it. Other than that its not that bad. I'm looking for a bellhousing and a shifter right now to do this same thing if anyone has one.