I put a TX750 swingarm in my '82 SJ and of course the TX750 chainguard interfered with the shocks. Rather than cut the TX chainguard shock hole, I mounted a Special chainguard by trimming off the TX swingarm front and side brackets, locating where a nut would have to be welded into the TX swingarm to take the front mounting bolt for the Special chainguard, drilling a hole at that spot big enough to hold an inverted 5mm flange nut, and having the nut TIG welded in the hole. You need to have a 650 swingarm available to measure how far in the new hole center should be on the TX750 swingarm - on mine, measuring with a square held tight to 650 swingarm tube, it was 1 31/32" - then add another 1/8" to compensate for the larger diameter of the TX swingarm tube. Just bolt the chainguard to the rear mount to find the right fore-and aft location for the new hole center. Just another way to do it - looks "factory".