Brief Description: Cut/Shape F-639B Seat Back verticl angle.
First thing I did was to mark these angles left/right and inside/outside. From here on out you need to keep track where they go.
I had a silver looking ¾” diameter washer in my bug box that was perfect to scribe the 3/8” curve radius. Then used the belt sander to create the curve. Scotch bright to finish it off.