Hi Steve,

They're adapters. They bolt to the existing hub and are studded with the Mustang pattern, the inside is machined for the Volvo centering ring, and the outside has a lip for centering the Ford rim.

I needed new lugs for the Ford rims, you can get them in a 4 pack at Pep-Boys (~$4/pack) or Wal-Mart (~$2), although Wal-Mart doesn't have the lookup guide to figure out which style you need (I have a spare pack that should have that information on it)

The only issue I had is that the spacers were ~4mm too big in OD, and they rubbed a bit on the stock caliper. You may be able to have the guy make them a little smaller, have a machinist turn them down a little, or just grind on them a little bit like I did.

Here are the specs I gave the machinist:
"I'm planning on using Mustang wheels (5x114.3, 70.3mm bore) on a RWD Volvo (5x108, 65.1 hub bore).I'm looking for 2 spacers at minimum thickness (19mm/.75 in.) and 2 at 25mm."

I haven't driven it for a bit, but iirc I was getting a little rub in the front at full lock, but otherwise no issues. I do have coilovers, and thus a smaller OD spring, which may give me more clearance than a stock spring.

I cut the lip out of the rear fenderwell, and hammered the inner lining a little bit, but at stock ride height I don't think it was really necessary. So far no rubbing issues.

I'll see if I can grab a few measurements that might be helpful for you tomorrow.

Adam