Hi Mark,
That gap in your 3rd photo is what I was referring to. Be careful as that large a gap could see stones etc flying out and up at a dangerous rate. Other than that the fitment looks good and well done. Perhaps get some steel mesh, cut it into a circle and fit it underneath the deck. (I'll try get a photo of the plate I mentioned in my earlier post) to stop stones etc flying up.
As I have lost an eye through injury myself I can tell you it's not pleasant and all care should be taken to avoid projectiles.
Pete.
