It depends on what BL was used. If a 1-2" BL was used not a lot other than what has been mentioned. If a 3" was used, the fuel filler neck has a spacer that will need to be removed, the steering cloumn may have a spacer that needs to be removed, or the shaft will need to be put back to oem settings(loosen bolts and slide the splines back in then tighten bolts, may have to do it on both the engine side and cab side of column). The break lines are normally pulled apart at the coil for a 3", some do it for a 2"BL as well.
You will also need shorter bolts, if teh owner kept the oem ones get them if you trade for the truck.
If the shifters were lengthened for the BL, you will need to shorten them as well.
You might also have issues with the exhaust if it has been raised.
How much work you have to do will depend on how well the BL lift was done, it might be more work then it is worth. It might also be easier to do a drive train lift, then cutting the sliders and bumpers off to fit the lowered body.
