New door woes

(sigh) My new garage side door is too big for the rough opening. About 1/2 an inch too tall. I’ve now got to chisel away at the top sill if I want to get this door installed. I blame the hardware store guy for looking at my measurements and saying “OK”. I also blame the people who put together this garage, because the existing door was at least 2 inches smaller than the smallest standard door. Also, the right side of the rough opening isn’t even plumb. The top width of the opening’s almost a half inch smaller than the bottom width. It’s going to take some time before I get this thing even into the frame, much less installed.