heavylevy wrote:HI DAVE & KATE
Pm sent
cheers
A big thanks to heavylevy

who explained it all to me.
I was under the impression that the strengthening bars inside the inner roof were solid aluminum and would need threading when i drilled the new bolt holes, but it turns out that the bars are hollow. When you drill your new holes, you can slip a nut behind the hole via small gaps in the corners of the cat-flap-hole.
Confused? I was too. It all worked out though, the holes are now drilled, and the hinges and bolts in place
Thanks again to heavyleavy and everyone else who tried to help.
Dave and Kate. Llandudno.