Correct mkII offset is 35.
Careful here though. Not just a case of how much the wheel sticks out.
Imagine looking down on the car from above. If your wheels are a different offset, they no longer rotate about the same point when they turn for steering... eg if they are sticking out more, they are further and further away from the centre of steering rotation which is basically the shock absorber (strut). Which means steering geometry is all messed up.
Secondly, if offset is further out or in, the suspension geometry is also messed up, because the wheel is carrying the cars weightfurther out (or in) from where its supposed to. If your wheels stick out further, the wheels begin to tilt inwards and the car rides lower on your suspension.
Before you know it, tyres are wearing unevenly, suspension bushes are wearing out, car is handling badly (sometimes horrific understeer), grip is reduced, braking is reduced... manufacturers put a lot more thought into suspension geometry than it might seem. Stick to as close as 35 as possible, and if you get the car lowered get expert tracking done or even consider adjustable track control arms for camber adjustment. Trust me its worth it.
When playing vauxhall games many will know that Vauxhall use a pain in the arse offset of 49mm. Many alloy wheel manufacturers do not go any greater than 38 or maybe 42, so most settle for that. However, after having 38's on a nova for ages the difference when I got a set of proper 49 courtney alloys was phenomenal. The car drove straight and true like it should again! a difference of only 11...
