I used lot's of double sided tape and started the bend at the trailing edge using a wood block as depicted in the plans. When I got it as flat as I could with the block I switched to the Flush set and my rivet gun turned down to about 45 PSI. Start at the trailing edge and move towards the leading edge without stopping. As long as your blocks are secured well this should give you a descent edge.
Clamped in place
Started the bend with a wood block
Completed the bend with my flush set and rivet gun
