I cut the forms so that they would be more manageable. Here are the inner forms about ready to go in. I attached the weld plates to some wooden blocks so that I could mount them in place in the form

I also added a filler strip to eliminate the sharp angle at the bottom of the arch. It's the triangular piece. Sharp edges in concrete tend to break off easy.

I also mounted some 3" PVC pipe to form a couple of holes in the arch. Later these will be used in hoisting it into place.