Well, the general user community on the Yahoo discussion groups say it's OK to use the P4 hinge as per plans page.
Completed the left/right SNX-F14-01 forward angle assemblies. Pilot drilled previously cut firewall attach angle as per plans, then transferred those pilot holes to the forward angle. Bent firewal attach angle to 94 degrees as per plans. Placed the cowl attach hinge between the fwd angle and the firewall attach angle, and drilled and cleco'd.
Cut firewall attach angle from raw stock; ripped to correct sizes on each leg. Cut hinge to correct length; cut 30 deg angles on each end as per plans. Finished the left F14-01 assembly the same as discussed in the above paragraph.
Fabricated SNX-F14-05 & -06 left/right upper and lower firewall attach angles. Ripped raw strength to correct widths and cut 30 degree angles on the end of each piece.
This finished SNX-F14 plans page.
Moving onto SNX-F13, I noticed that the windshield bow hole was not cut on the right upper longeron. Using the correct hole in the left upper longeron, transferred the dimensions and drilled it to size. Elongated the hole to 21/32" and deburred.
During this task, I noticed that the predrilled holes in the angle were just a tad small, making it difficult for the cleco's to fit. Up-drilled all 1/8 pilot holes to #40.