Laying the part horizontally on a square tube the same width as the inside of the "U" makes assembly/disassembly fairly easy. Otherwise, the vertical spare and smaller frame becomes juggling. DISADVANTAGES: * For reasons of strength, the thread must have at least the diameter of the screw. that's about 1/4 the normal depth. Instead of the threads (just over 2 threads) of the stop piece, a nut should have been welded to the stop piece. * Easy to cross thread. If you do this, just drill and add…