thanks demoe,
I was looking at some aftermarket wheels, spoke to a guy in the states that was selling wheels for a ferrari 360, he told me they should fit a 4200 but to be honest he sounded like he just wanted to make the sale. Later looked on f-chat and it seems the sellers have a less than great reputation in the US.
I had assumed that given the high levels of consumer protection and threat of litigation that we in the UK(or certainly I)perceive the states to have,that dodgy traders would not prosper there but I suppose we all have the same problems.