oewheelsllc.com offering this width at this price means I can forgive the C6 style.
But the riveted black Z06 version is only $106 for anyone who can't.
And DiscountTireDirect.com has some Nankang 275/35ZR18s for $105 each.
So that left me trying to figure out backspacing.
The 10.5s have 8.03 inches, so what spacers?
Rear first, 315s on 11s fit well with 7 inches of backspacing,
so for a 10.5 that would be 6.75, or a 1.28" spacer.
For the front, the '92 Firehawk came with 1LE brakes and 275s on 9.5s,
with 5.5 inches if backspacing.
And 1LE hubs measure 4.63", while my common versions are 4.31"
18s fit over the tie rod ends, so the extra inch should all go inboard.
So until I do big brakes, a 1.8-inch spacer should be closest.
adaptitusa.com offers 1.8-inchers for $ 114.50 per pair, lucky coincidence.
for the rear, their 1.3-inchers would be $ 89.50 per pair, or
there are several choices for 1.25-inchers from other sources.
So wheels plus adapters, divided by 4, averages $ 136 per corner.
Still not a bad price to be able to tuck 315s up front, IMO.
And if 315s don't tuck with that spacer, well, there's 1LE hubs, then..
Baer rotors add another 0.3", so will need the spacers machined thinner anyway.
Looks like I'll be selling those Kumhos I never bought 17-inch wheels for.

 

Just sold my set of virtually-new 275/40R17s, so that's a little progress.

 

I've got a set of DD C5's, not exactly the same wheel, but same backspace/offset. They are 4th gen offsets, so a 4th gen rear or at least a 1.5" spacer is needed in back. Front requires that as well I believe if running stock brakes. Subtract the thickness of your rotors if you are running hubs with slip on rotors.


This is just barely catching the studs on a stock (3rd gen) rear, and it hits the wheel well. I haven't swapped my 4th gen rear yet (or bought tires or front suspension parts), so I'm not too sure weather I'll end up needing a spacer out back.