3 hours to figure something out ??? He must be paid hourly.
I have had issues "getting the car onto the alignment machine" after lowering it 2 inches + ... they had to bring out some wooden ramps to drive the car onto the alignment rack. It depends on your shop and their resources / knowledge.
When you lower the rear end substantially, the alignment goes way out of spec. Yes it is possible to run out of adjustment if you are too low in the rear end, at this point you need to slot the upper control arms bolt holes because the alignment adjustment isnt on a linear ratio, its more of a curve when you go to the far end of the adjustment it goes WAY out.