Custom lower engine mount forward shim

The tips of the connecting angle between the bottom skin and the firewall sits underneath the firewall vertical stiffeners. A 0.63mm gap is therefore created right near the AN5 bottom engine mounting bolt. The design as given expects this gap to be closed up when tightening the bolt and the consequent distortions to be pushed elsewhere. I decided to avoid this unnatural situation by creating a shim from 0.63mm sheet that fills this gap. This shim would be inserted between the vertical stiffener and the firewall, clearing the connecting angle, and making use of a few of the existing rivet holes and the AN5 bolt itself to positively locate it.