You can see the difference between the "offset" 1952-1954 and the "parallel" late-1954-1969+ brackets below. What isn't obvious is that on the -52, the holes for the fork tubes are not at the same angle as the hole for the fork stem.
- -52 upper fork bracket (offset)
- 52.jpg (93.94 KiB) Viewed 12778 times
- -59 upper fork bracket (parallel)
- 59.jpg (74.16 KiB) Viewed 12778 times
The 1959s used the small headlight, no switches on the upper panel, and the larger speedometer, so the mounting tabs were different. The late 54 to 1958 had a bracket (-54) with the same front tabs as the -52, but it was parallel.