ES2 Plunger Rear Wheel Fitment

I've been struggling to assemble the rear wheel correctly on a 1952 plunger.
I the photo's attached I have stuck the measurement between plungers at the axle forks (8 3/4 ").
The LHS side of the wheel seems OK, but the RHS cannot accommodate the spacer and the adjuster.
I'd really appreciate an experienced pair of eyes looking at and weighing in on what could be wrong there.
Thanks in advance

Chris