Yeah you don’t have to remove the quarter to replace the outer wheelhouse if you’re removing the inner wheelhouse. Makes the spot weld removal and welding a bit trickier but it’s not impossible at all.
I replaced a whole section of my outer wheelhouses to remove the “bump” in the outer wheelhouse and make room for more tire on my Duster, and I did that with the quarter and inner wheelhouse in place. Kind of a pain, but less work than doing the whole quarter.