It took maybe ten fittings of the top cowling until I was satisfied with the fit. I created space at the spinner backplate by shaving maybe 1/8 inch off the back of the top cowling. This pulled both top and bottom backwards.
Pictures 1 and 2 show a couple of joints. Minimal gaps. Picture 3 shows the spinner gap I managed to create, about 1/8 inch, which should be sufficient.
The overall fit is not perfect. There are a couple of small gaps and the whole cowling is maybe 1/8 inch too far to the right. I'm not sure it's worth the effort to fix. And I could well make things much worse...
That's the good news. The tough bit was drilling holes through the cowling into the top cowling hinges, particularly along the sides. I had previously put black dye in the resin, which made it difficult to see through the (previously) translucent fibreglass, even with a backlight. Don't do what I did!
On reflection, I should have carefully measured outside to see where to drill holes. In the event, I drilled about 8 holes much too close to the hinge of the hinge if you know what I mean. I subsequently drilled some more holes to make sure that everything was secure, but I now have an unsightly higgledy-piggledy row of rivet holes. I'm hoping that these will disappear under a layer of paint. Too embarrased to take a photo...
