Acceptable offset?

[Savet]

I've been searching, but haven't found the answer to my question.

I'm looking for a 2nd set of wheels for the Elise (base suspension), and I've noticed some members are running the Rota Slipstreams or Rota Torque wheels, but the only ones I've been able to find have a 40+ offset. I'm looking at the 16x7 front wheels.

When I look at the wheels offered by sector111 and tirerack, I notice the offset is much lower for the 7" front wheel at around 31. If I was to get a front wheel with a 40+ offset, am I going to need any sort of spacer or lug modifications?

Thanks for your help