LML Denali, order you some Meguiars All Purpose Cleaner Plus from autogeek.net. It is super concentrated so order the measuring system that is optional. It will last forever and should get your stain out!!
2016 Summit White 2500HD Denali Duramax CC 4X4. DRP Sump, 4" turbo back exhaust, 3" MBRP down pipe, AFE Momentum HD Intake, FASS 150 Titanium, Motor Ops with trans tuning, Edge Monitor, AMP Steps, CST Performance 3-6" Lift, CST Performance Dirt Series 2.0 Resi Shocks, Fuel Forged FF07 22x12 -51offset, 325.50.22 Nitto Trail Grappler MT, color matched everything.