Anyway - I will be setting up the car soon, and want to know a good start point. I realise I will make adjustments once I start doing a bit of testing on some airfield track days, but want a place to start from.
So what are the best setting for camber, castor, ride height front and back (and measured from where), spring rates (don't know what's on my car as it's come part build from SSC and was originally designed for a Zetec though I can take a look and see if it's marked on the ends - the Nissan engine must be a bit heavier), and anything else I should be doing.
I'll be ordering an anti-roll bar from Tim as well so it would be good to know the best way to set this up too.
And yes, I know I'll need to take into account my humongus back wheels
From a set-up novice
Jasper
Well your ride height will be governed by your wheel arches to a degree . If your main interest is endurance rallies ride height could do with being a touch high , say 150 to 160 mm then normally I'd say 20mm up on that for the rear .(170 to 180 mm) That will give you a balanced car , leaning towards oversteer. BUT with rallies , LUGGAGE will play a large part plus passenger/navigator so I'd opt' for 225 lbs rear springs then 250 lbs springs up front plus an anti roll bar set at the weakest hole. With the Nissan you'd need 275 to 300 front springs to stop rear diagonal lift on cornering IF YOU HAD NO ANTIROLLBAR 
It would be twitchy in the wet with those .
Anyway measure the front ride height under the lowest chassis rail --- the shocks mount onto it 
The rear ---- measure where the alluminium floor sheet meets the steel seatpan(they're rivetted)under the drivers door. The car should be driven / pushed about / bounced a little , after you've jacked and let it down , otherwise it will be high. Do this each time you adjust.