Today I realized that you should not always follow those who have lead before you. I almost made the same mistake that another builder made in the lower firewall. I installed the F138-B gusset plates on the inside wherease they should have been on the outside. With the gusset plates on the inside it became apparent that a shim would have to be made. Fortunatelly, when I returned to building this evening I realized that the manual calls for the plate to be on the outside therefore making any kind of shim nonsensical. I therefore fabricated 2 new gusset plates out of 2024-T3 using the previous ones for an outline and proceeded to clamp, cleco and drill those plates using the existing holes. I finished drilling and cleco'ing the holes. Next will be deburring and priming of all the parts cleco'd in place right now. I also figured out how PF-194 and the support tubes mount to the frame.