'06 Solstice Base
The info I just googled says the center hub diameter is 65.1 on both the Solstice and the Saab wheels.Jon,
Looks like you found a great deal on the temp spare. Not much on the Saab 9-5 on eBay when I just looked but nice 9-3 choices. So...I looked up lug patterns for the 9-3, 9-5 and the Solstice. Here's what I found:
Model Year O.E. Wheel Size Bolt Pattern Stud Size Hub Center Bore Offset
9-3 99-UP 5x110 14x1.5 65.1 H 9-5 99-UP 16x7 5x110 14x1.5 65.1 H
Solstice 2009 / 5x110 12x1.5 65 34 to 45
Sorry about not getting the columns to all match but they do in my original layout. Important thing to me would seem bolt pattern and center bore size for the temp spare. I'd not use it on the street.
What do you think, 9-3 OK?
I know the spare is a snug fit on the hub.
The lug nut's taper seats and torques against the taper of the hole in the wheel, so does it matter if there is a difference in stud diameter between the Solstice vs Saab?
(You're locating on the hub, and tightening down with the lug nuts.)