Thanks everyone for the kind comments, much appreciated!
As for the strut technique, I'm afraid it's really nothing too fancy: a steel ruler and a pair of long-nose pliers, plus a lot of trial fitting. It certainly helped that the holes in the upper wing gave a snug fit, so I could fit the two supporting struts at the front, then clip the wing on to check the alignment. It literally would stay in place with just those two and no other help. Once I had those two struts in place, the rear ones were simply cut to fit the gap!
Today I tackled the exhaust. I started with an Aeroclub item, and removed the individual stubs one by one, drilling the exhaust and fitting a piece of brass rod as each one was removed so that the spacing was kept.

I also chopped off the rear end to shorten it a bit....

and the end result:

So the next job is to fit the Spandaus and the cabane rigging wires, and make the rest of the struts.
Thanks for watching!
Ian