dssur
+1y
more offset, 1 inch = ~25mm
for a mightly max you need FWD offset wheels. on an 8.5 inch wide wheel you would want 7 inches of backspace or +57mm offset.
This corroborates what you noticed, if they are +15 and stick out an inch and a half, 1.5 inches is 38mm, + the +15 you already have, equals around +53 to tuck...
Good luck. I havent seen anyone besides the billet companies make a 6 lug rim that will tuck or have anywhere close to FWD offset.