Looks like plastic pins and a couple of metal clips at the bottom and a plastic channel at the base of the wind screen. The wiper posts go through as well. Is there more than that securing the grill/cap?

Thanks Rick

Temp gauge reads 12 o'clock but no heat to the cabin. Blower work fine, trace amounts of heat detectable at vents. The car has to be parked next to a long needle pine that sheds buckets of needles and the cowl grill and water drains are exposed to them. Drains can be cleaned by hand for the most par...