I did the headers on the Model A by fit, the rest of the exhaust I did with that neat little multi piece plastic tool. Which probably woulda helped a bunch on the header. 1.5" tubes in to a 2.5" system. The collector is a 1.5" x 2.5", Summit Racing item. Some might say overkill for a V6, but, it is a blown V6. Simple X pipe. Took some 45 degree tubing and sliced the corners off. Took my time, checked everything twice before tacking. So far I am just in front of the rear axle. I'll do the rest the next time I remove the body. Magnets help for holding stuff along with muffler clamp tools.