Copper from the standpoint of corrosion is superior to steel, but vibrations will fatigue it at the flare. Better use steel, stainless steel. I always tied the front tube to the upper part of the inner fender portion above the A arm section, right at the top where that piece makes the tight upper bend. This is the section spot welded to the inner fender where the upper shock stud comes thru. This is where all the load is on the front end, and in effect triangulates the front bar at that point. Nice job for a first time. Weinerboy1.