I am pretty much still on that - I tried the small diffs front and rear for a while but have gone back to the overdriven front which on loose tracks is certainly nicer to drive. I've tried the machined pistons, which weren't much good - they change the damping too much.
The main thing was getting it reliable - I had a lot of problems with little stuff like wheel nuts and ball cups.. Since going to the HB cups (and balls) and now HB serrated wheel nuts - I've not had any problems.
I am now using the big belts / pulleys. I've written a little article on these which needs finishing off. The car is still performing brilliantly and it's one of the few that can take being thrashed into a wall without damage. A good thing if you're me!
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