The console, for some strange reason renamed bracket in the B20 catalogue, is displayed on the brake page, not on the posted front suspension page. Also note that Oliver had an 1800, not a 122. The diagram below shows a B20/four pot caliper front brake. The console/bracket is part nr 16.
Backing plates also differ, yes, but I think the existing plates can be modified to accept the later brakes. Brake line support is the big difference but I don't remember if the little console still was welded to the backing plate, like the single circuit style, or mounted somewhere else on the spindle. It isn't that obvious in the catalogue diagrams.
/Martin
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'65 121, '73 165
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