Rear leaf spring is very easy to 'adjust' by removing/adding leaves to alter the ride and ride height.
I started by taking out the top three 'loose' leaves and putting an 80mm lowering block between the spring and diff. I also cut down the top three springs and used them as shims under the spring to lower it even further -
I soon removed the three shims as it was obvious that it would be too low even before I fitted the body.
Once the car was on the road I found that, even though it looked great, the car was too low both front and rear and kept fouling the ground.
It was also rock solid at the front and just too firm at the back for my liking, so I set about making some changes.
I replaced the 175/70/14 tyres with higher profile 175/80/14's and changed the 95mm cut down 220lb Vitesse front springs for 150lb Mk1 Spitfire fronts cut down by 25mm and a thicker arb, which raised and softened the front.
I then tried various combinations at the back - removing the next three leaves in the stack, switching the 80mm lowering block initially for a 50mm, then just the three shims (15mm) -
I eventually settled on replacing two of the last three removed leaves with no lowering block at all. This has made the ride and handling spot on, it's compliant with no discernible body roll, it's given me enough ground clearance and left the stance looking not too shabby either -
Good luck!