I'm with Cajunator.... try getting some heavy duty EasyOff oven cleaner. Saturate the spots and cover it with a plastic bag for 12 hours or so. Then rinse.
2 - 22.5" WSM , Weber 22.5 Performer and a very tolerant, very Beautiful Wife!!
[B]Black[/B] & [B][COLOR=Blue]Blue[/COLOR][/B] Thermapens!!
KCBS CBJ & TC #55078