Thanks. I'm not doing anything to the cowl vent, I'm just correcting the hood/cab mating edges on the driver's side. It should be a straight edge, as it apparently was in the original issue of this kit. Later issues have the same cab as the DM800, with a step to fit the steel hood. To be accurate, it needs a piece cutting off the cab to create a straight edge, and a corresponding filler piece added to the hood. Even with the steel hood, there should still be a straight panel line there.