I have a 100+ year old house that I have started to remodel. I have knocked out all the old plaster and lathe on the walls and am now wiring outlets before putting up sheetrock. I planned to use 1/2 inch sheetrock, but after taking off the wood frames around the door and windows, I measured the gap between the lower sill of the windows to the stud is more than 3/4 inches. Can I use shims on the studs next to the windows to decrease that gap down to 1/2 inch? If so, would I also have to do that on all of the studs on those walls. I want to make sure of what to do so that when putting in the outlet and switch boxes, I leave the right distance for the sheetrock. Thanks!