I have some casement windows to install and have some questions related to the essential brick moulding and installation with dripcap flashing

the instructions for the brick moulding BMC show no fashing over the head trim and the gap caulked. i think it would better to add a rigid drip cap extending under the house wrap and over the head trim. The gap not caulked. would this be a better way and worth the time? The BMC is fiberglass and would not be effected by water but i thought it would be better.

The window has a build on pvc drip cap flashing. Should i remove it and add a rigid cap? Would the thickness of the trim coil effect the BMC installation if i add it?