After going to Ford Fair I've got the itch for one of these as I quite like the look of them.

Basically looking for a little bit more info on them. I know they can go a bit rotty round the edges and there's a phase 1 and 2. What are the difference's between the two? What other things are there to look for? What modifications do they respond well to? Would I be better off going for as late a car as possible? (51/02 plate)

Any help and info is very much appreciated thanks!