There are a one or two cars floating around running these, but I believe they are running conversion spacers. I'll see if I can dig up the picture once I'm home.
If you were able to find away around converting the MX5's wheel hub to 4x114.3 (without bolting a 25 or 30mm spacer on) you should be able to run the 14x8 -11 with flares. Would probably be able to pull off the 14x9 -14 also if you had some big flares/stretched tyres/etc. Would look extremely epic in my opinion . Don't think you'd have any luck with 14x12 -62 though Seriously, what car would that fit on...