...That's why I have a set of 2003 Nissan Frontier SC wheels on their way. 16x7, +20. Cast, but strong and light at 19 lbs. I'll pick up 36mm (1.5") of track width, yet I'll still be able to run the narrower tires that I like.

I might be the only fool on earth who puts on the 18s in the winter, and saves the 16s for summer.

Being that you're on the righthand side of the Atlantic, you should have a lot of choices in the lightweight wheel department. Compomotive and Kosei immediately come to mind. I couldn't find a US dealer for either.