Bronze skin fitting - anti rotation nib?

[West Coast]

Following on from recent posts, i realised that my newly purchased 3/4" bronze skin fitting has an anti-rotation nib on the underside face of the flange - presumably this is designed to engage into a suitable slot formed in the grp hull. I am a bit wary of making such a slot - don't want to weaken the hull round the existing hole, or am i just being over cautious?!

 

[doug748]

It is often enough to take a divot out of the edge of the hole with a square file, you may need to nip a piece out with a 1/8th in chisel, to cut the inner edge square. It really is a only a tiny bit, but I would treat the raw fibre with a coat of Gelshield or Araldite to seal it.

 

[West Coast]

Cheers - seems a good way to go.