Yes you should check the offset before you buy some tyres. I tried some TR6 steel wheels on my Mk1 but they stuck out by a couple of inches (but my car has MK 2 rear suspension) so if you have MK 1 suspension you might be ok. My car now has 15 x 7J wheels with 205/60/15 Yoko tyres the clearance between the tyre & wheel arch lip is aprox 15mm. I brought my wheels from CW not cheap I know but at least I knew they would fit.