Mulligan
+1y
I take it your 99 sierra is the obs being 88-98 model trucks? If its the newer 99-06...my crew cab has a 3/6 drop with helper bags in the back (you need em with a 6" with the air out it bottomed out everywhere and smacked the notch) I have 22x9.5 rims with a +30mm offset and it looks and tucks perfectly...most 99-06 rims they sell with a +20mm offset but the guy got me the +30 because it was going to be lowered.
my bagged 97 (obs) has 20x8.5 in the front with a 5.5 backspace, not sure on the offset