15x7 et13 fitting.

Hi Guy,

First off I have searched this but get some varied answers. 

I have a mk1 jetta that's being rebuilt just now. 

Does anyone know if the jetta and golf both have the same arch gap?

I am trying to find wheels and have came across 15X7 ET13 ideally I was looking for this rim in ET25 but beggars can't chose as they say.

How much will these poke and will I and up having to run stupid stretch to get the fronts to fit. 

I don't mind rolling the arches but with the coilovers I don't think that will be enough. 

Any advice or even better is there a way to work out the    measurement from the rear of the hub to rim of alloy?

Cheers and sorry it has square lights and a boot.

Craig