Thought this may be useful to other members when it comes to choosing wheels and tyres - they helped me out and it’s always good to see what people have already done to see what’s feasible.
Fitment industries gallery of wheels and tyres on people’s cars with specs, suspension, tyres and whether they rub or need additional work:
https://www.fitmentindustries.com/wheel-offset-gallery?sort=yno&year=2014&make=Mazda&model=MX-5+Miata
Calculator that shows prospective wheel position using current and proposed specs:
General tried and tested fitments according to bofi racing:
Info about wheels that work from good-win racing:
https://www.good-win-racing.com/Mazda-Performance-Parts/MX5/Wheels-Tires.html
Hope these are as useful to others as they were to me 
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