Small pulleys, big effort.

The blueprints show the elevon trim cables running  along the right cockpit wall to the rear. Within easy reach of the pilots ellbow, which is not exactly ideal.
Surprisingly, there are none of these cables to be found in the cockpit of the original aircraft. Obviously the layout was altered during the construction of the aircraft without updating the blueprints. It took some CAD  work to make the cables run below the cockpit seat.  The result: A pair of pulleys on a carrier, machined from a solid block of aluminium which functions as cable guard at the same time.