Good afternoon all.
Just after some info on offset, I am about to order the Superlites for the car Which is a Mk2 4 door, I will be going for the 15x7 i understand its 4x108 and have been reading ET12 is what everyone is saying just need clarification before I order? the guards haven't been rolled yet so 195/50/15 will be fine(what I've read) but would like 205/50/15. the panel beater can do them if i want, also Superlite (GTR's) are wanted but legal issues are clouding my decision!! should i bother or just stick with the norm.
Kind regards
Matt

I'm thinking 15x7 12P would be fine with 205's without rolling the guards but I'm sure others can confirm.

I'm running 205/50/15 on my van and no rubbing,i'm thinking of going 215s next time with the rear guards rolled.But i'm running 15/6.5 rims   

Based on my calcs and measurements, it would be close, but theoretically doable.  For reference, I measured the distance from the face of the wheel hub to the inside edge of unrolled guards at 95mm (both front and rear, on a Mk2 2 door).  With 205 tyres on 7" wide wheels with 12p offset that would leave 4mm clearance (ignoring the effect of camber, toe in etc.) between the outside edge of the tyre and the inside edge of the guard.  All of this assumes the dimensions of tyres, wheels etc. are millimeter perfect, which they probably aren't.

That's great news and a very informative answer , so i will get him to roll the guards so there is no chance of any rubbing and order the 7's   :-))will put the order in next week.
 

The size, width and offset will not be a problem. I have 195/50/15 on mine and they clear everything.  205 wont be an issue on the rear but the front will most likely foul on the firewall on full lock.  Not the end of the world but will leave bare metal on the body where the tyre rubs

I'd stick with 15x7 12p and 195/50x15. 
 
1) If you have a RS2000 these will still rub a bit on the nosecone bottomplate at ful lock
2) If you want to lower / put in adjustable strut tops you'll run into dramas earlier
3) If you get a quickrack, 205's will be hard work to steer at low speeds
4) 195's still are wide enough to look great and fill the arches nicely