Thanks guys. I'll try the vent windows, never thought of that. Seems to be worse with the door windows down. Mine was originally A/C but most of that is gone and the ducting under the dash. The heater blows hot though and keeps the windshield clear so I haven't bothered with it much. I do wonder about those rear spoilers they put out back, seems if it ducted air from over the roof inwards it might help. Maybe I'll try a 2x6!