Fitted the lower longerons to the Forward Floor Assembly. Match drilled holes, countersunk for (2) AN509 8R12 screws in landing gear weldment. Dissassembled, deburred, recleoced the lower longeron in place and temporarily bolted lower longerons on both sides. The process took a great deal more tweaking of the various twist to get the fit that I wanted but I am pleased with the fit.