Hamish, looks like you were there the day after John of Auto Shennanigans! His summary of the speeds for the current record holde are frankly terrifying. It rather puts into perspective what a 22 second time actually means I rather like his Youtube channel, worth looking at a few more

They are 5.5 x 13 Dunlop steel wheels with 185/60 tyres. They have slightly more offset than the similar Triumph 5" wheels along with the wider rim which puts them further out in the arch. And the lower wishbone brackets are spaced out from the chassis with 10mm blocks each as well which all adds about an inch to the outside of each tyre over. Back end has the short halfshafts on the swing spring as the 5.5" are too wide with the long halfshafts without wheelarch surgery.

The wheels are intriguing me, like std wheels but wider? Or is it just the angle

That’s the one my wife thinks works best.    video of all runs  to follow. 

Isn't it just!

The last one I think. 

That's a good looking spit

This is my fibreglass one. 8kg including the back window.  The carbon one should save a couple more kilos.

I'd like to, egret!   I'd need your metal roof to make a mould. John

There's a slight lump at the rear on the base of the passenger side of the windscreen, but I've not fitted the locating cones yet.  If I can tease the upper rear sections of the bonnet slightly further apart, then it'll get better than the steel one does.  Then I plan to cut some lemans inspired holes in it, and make some stiffening ribs so it's not wobbly. Oh, and @JohnD I'll happily take a silverback inspired hardtop if you've completed all of your other projects!