Many thanks for reply.
I purchased all the adapting filler necks etc, just need the exit through the sde grill.
Car is a ground up restoration so no issues with access for cutting body, literally only need the side grill.
Would prefer an OEM part but if I cannot source one I will have to make one as you have said. I do have a friend who is very local to me with one on his car so can use as template and look to replicate this.
Thanks again - Tony