Okay, they are mounted. It is done and I have a definitive answer:
First thought, best thought. You have to just mount them outside of the rear rack. The screws that were used to mount the rack are not long enough with the added width of the side mounts, so you need to buy four new screws. They all need to be 8mm x 1.25mm. Two of them should be 90mm button top; two of them 80mm socket flat head.
The mounts come with arms to relocate the blinkers, but my blinkers were already out of the way, down by the license plate. Not sure if that is because H&B is a German brand and this is a Euro vs US set-up, of if my bike’s previous owner moved the blinkers when the rear rack went on. But either way, the relocation arms are unneeded and unsightly, so I’m just took a hack-saw to them and cut them off to streamline the look a bit.
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