inspector507, you are correct, i am using the master rib and the ribs are closer to 10" apart, so when i cut it, unfortunately, the cut end will be whats overhanging the gables and will be visible, i wish there was a way to put the cut end under the previous panel, but this panel actually overlaps the previous one.. I guess im going to go with the clamping the pice of wood to the metal and using it to keep the saw running straight, but im afraid i wont be able to find a straight piece of wood, every last peice we have bought for this project has been bent and bowed, every last one, so im gonna have a time finding a good straight one, ive been trying to think of something else to screw down to the metal to use for a straight edge., no ideas though.
I thought of another problem also, the ridgecap, it sets on top of the high ribs on the metal, on the rear gable, the metal im cutting will end up flat on the gable, therefore, the cap wont have the high ribs to sit on right at the gable end, should i get some sort of spacers to put under it at the very end to act as the ribs would have? at the front of the building, the roofing starts with a rib, at the rear of the building, the metal will end with a flat section.