I ALWAYS iron down all covering edges before beginning contruction of any A.R.T.F.
It's the first, and one of the most important jobs to do.

Time is money to the manufacturers. They don't (can't) press the edges of the covering properly beacause it would double the
covering time. So, you have to do it. As well was putting extra cyno on firewall, u/c fixing plate, wing fixing plates.