Ok after a bit more research I learnt a few more things about springs rates...
Taking the VWR kit and KW Clibsport kits which are 90-170 front and 70-170 rear, this relates to 90n/mm spring rate over free length of 170mm and rear being 70n/mm.
This equates to something 500lbs front and 400lbs rear, which after talking to David at GAZ was a stiff track setup, which the two kits quoted are...
So after some delving, and some help from Hassan at Awesome Gti, he came back with info from KW that the V3's have a spring rate of 50.56n/mm front and 44.17n/mm rear which equates to 285lbs Front/250lbs rear...
As I wanted a slightly stiffere set up between the two, I have gone with 365N/mm front and 310N/mm rear, which is some 20% up on the V3's but no where near as stiff as Clubsports...
David will set up a good window of damping adjustment around these spring rates.
Let the 3week build time commence! ;-)