wheel offset

I just got a set of '86 951 brakes, and rear trailing arms. I can't decide if I want to put them on my Ghia or not. To fit under my factory wings, what offset Porsche wheels should I use? I've read that 993 C2 wheels will fit under stock Ghia fenders.

I'm looking at a set of wheels on ebay with these specs:

"Wheels are 18" X 8" ET50 and 18" X 10" ET65. Tires are 225/40-18 and 265/35-18." (seller quote)

[ricola]

It's the rear end that is tight on a ghia, the most I've seen practically tucked under are 7J width, no chance of fitting 10J!

I realized that too. I figure I was just enameered by the 997 Carrera S spokes. What have people fit under a Ghia, with what offsets? I'm thinking in the 18~19 inch range.