Anybody keep track of body work / panel replacement hours?

how many hours of work do you guys think it will take to replace an entire rear clip (middle of wheel arch to the very back) as all one piece? Assuming you had the spare rear clip and could trim it to where you wanted to. My 66 Dart has rusted lower rear quarters, pinholes in the spare pan, and a dent on the lovely side curves near the passenger tail light. I'd also like to use a 65 bumper which means I need a valance. I have a 65 rear clip ready to go, but I'm curious if my body shop is going to want to replace the whole back end, or do it in pieces. How would you guys that do bodywork approach that?