Hi. I've tried looking around for the answer to this, but seem to be getting more confused, not less.

I currently have 205/50 - 16" tyres on a 6J" rim.
I am looking at fitting 215/50-16" on a 6.5" rim (dont ask why - acquiring a set!)
I want the second set b/c i intend doing some track work and eventually to fit motorsport tyres to the new 16"x6.5" set.
The 215/50-16 is a very hard to find tyre.

Two questions:
1. Will 225/50-16 fit without rubbing? Or will i need to go 225/45-16 or is 225 just too darn wide?
2. Will 205/50-16 onto the 16x6.0" rim? Or is the rim too broad for the tyre?
I'm not hugely worried about change in speedo or gearing (within reasonable tolerances - say 5%). I also appreciate that there will be differences in ride/handling with the varous size tyres.
Thanks in advance

, and for any other suggestions.