What gap do people have for there exhaust to fibreglass? Mine runs out of the bonnet and don't want it too close but don't want a massive gap there

How much room have you left?

Thanks

I would suggest that you make a fairly big gap, say 3/4", and then make a nice trim from stainless, or even alloy to trim the hole and leave say 3/8" clearance. Plus side of doing it this way you add some stiffening to the GRP around the opening. Just how I would do it, others may disagree. HTH Ray