This might not be helpful at this point, but I don't think the coupes need that aluminum panel mounted on the firewall. That's for the 818S that has the humps in the bodywork there.

Also, I'm curious how you engine wiring is routed. It looks clean! I have all my wires running over the engine on the cross rails and I've though that it looks a bit busy.

Curious to see how the wiper comes out. I'm using the Forma Cars monowiper kit and I'm quite happy with how they designed it. Could be something to look at even if you're building your own.