Mike
Gutted for you after the hard work you have put in to get this bus on the road in such a short space of time, you could put a rubber edging over the cut rear wings for the time being if you didn't want to fold the edges.
Sounds like the tester didn't want to pass it anyway, good luck with the retest.
GSF do a complete replacement drag arm for the steering for about £25, I know as I had to fit one as Arnie failed his last MOT on the same thing, made a massive difference to how it drove and I hadn't spotted it either!!