Thanks for the reply Pete, I have phoned Faulkners and spoke to Andy - very informative and he said along the same lines as yourself, including taking measurements and photos with old spring units in place - too late! units are on the bench, car on axle stands. However I do have a workshop manual so I will check sizes etc. New springs £80 each - ouch! made to order - seems extreme.
Also thanks Lawrence for spring sizes - even more confused now as Vitesse workshop manual stares that spring size is 12.49 free length load 940 lbs
Cheers Andy