Cut the P-3 hinge to 10” and cut the pin to 10 ¾”. Bent the end of the pin 90 degrees. Drilled the 1/8” “locater” hole in the hinge and clecoed to the seat back and 832 angle. Lined the hinge up parallel with the bottom of the seat back, clamped in place and drilled the opposite end—then match drilled the remaining holes to 1/8”. Clecoed the seat back, 832 angles and hinge together. Reamed all holes to #30. Took everything apart, deburred all the holes and edge finished the seat back.