A quick update, we're now 2000 miles down the road, I've been to South Wales, and the Goodwood FOS, and used it as a daily driver (though luckily I work from home) no problems. I will be going to the Silverstone MotoGP camping, I reckon if I take everything I can get on the motorbike it should fit, anything else I squeeze in is a bonus.
I fixed the sunroof strip, the dreaded autoheat (helped by the guys at I.B.) and the original alarm, but no real issues, and all is dry inside. I did spend 2 grand on a carport in a moment of paranoia, an outdoor cover is coming before winter, though I may even SORN and store her through the worst of winter - I'm going to buy a cheap runabout for the salt season.
Unfortunately it does seem to run sweetest on BP Ultimate Unleaded, £1.55 at my local garage.
It sounds like a tappet is clacking away, I have the gaskets and the gapping tool ready, and may take the plunge next weekend. I squashed a finger playing trains last weekend (I volunteer on our local steam railway), as the job looks fiddly with 10 fingers I'm giving it a week for the swelling to go down, rather than try with 9.