simon's learning what to do with the polo thread
other than tyres, it seems like the first place to start is making a stiffening beam for the back-end, and I suppose some poly control arm bushes, maybe make a strut brace for the front too? As I said, I nearly made a rear stiffening beam - I wish I had, I didn't think it'd be as bad as it was...
I like your TT ball joint modification, except that the strut top bearings collapse (right?) can you replace the tops of the standard struts with something that can handle the change in angle? maybe machine an angled plate to sit on top to correct the angle?
oh - and I think I want some 15" wheels - since it's my daily, it might be smarter in the long run for me to get some 15" wheels and cheap-ish track tyres (even 2nd hand race tyres) rather than put expensive tyres on the 16" wheels for the ~25,000km I do each year plus trying to compete. I've always had separate competition and road tyres for the mini
if you were on a (very) limited budget, where adapting or fabricating stuff is easier than buying, where would you start?