I guess I'd just cut a hole in the siding that's 10 3/4"h x 16 3/4"w.
Put flashing at top of hole, use 2x2's inside to support weight of window, and caulk window to inside of siding.
.There's more but hard to type it out, could make you a drawing, but not today.
Put flashing at top of hole, use 2x2's inside to support weight of window, and caulk window to inside of siding.
.There's more but hard to type it out, could make you a drawing, but not today.