Well one way might be to take the inboard wheel collar and grind it's side so that it is uneven, effectively making it an eccentric, also grind another to mate with the first. Put the two together with the "eccentric" sides together. Now install both on the inboard side of the wheel that is to be braked. Lock the further most inboard collar as usual, and put a washer in between the wheel hub and the "brake assembly" (that you have made). Install the out board collar as usual but adjust clearance so that when you rotate the innermost inboard collar the clearance is diminished thus making a clamping force ultimately applied to the wheel. The method to actuate would be via cable routed along the strut guide by "eyes" soldered to strut. Also the set screw tap, for the collar to be actuated, may be used for a control horn installation similar to what is used for nose wheel steering.

Brake adjustments would be accomplished by moving the outside collar in or out.