Excellent and I am looking forward to the rest of the build.
A swing jib will help you with those cuts, but you can also do it by hand fitting the pieces together. It will take some fine tuning and more time, but I have done several by hand it it works fine. Cut and sand your first arc piece, then trace it on, cut and sand until it fits perfectly with the lamination spacers in between the two pieces.
One other note, welding on the large single nut on the other side of your form brackets will help (as you wont have to mess with a wrench during the glue up)