Deburred all the angles that attach to the firewall and match drilled them.
We couldn’t find the F-801L backing plates that attach to the front of the firewall in Van's inventory or hardware lists so we had to drive home to consult the Internet. A search on VAF quickly revealed that they are located in hardware bag 2391.
Back at the hanger we found the unlisted hardware bag 2391, but it had only one F-801L in it! Fortunately we had one so it was easy to make another patterned from it.