Thinking about buying a set of these for my '91 RS, but have some questions:

https://www.ebay.com/itm/4-New-16X8-...1Z24hn&vxp=mtr

1. Factory front and rear wheels are different, yet all the replicas look like they're the same all around. Do I need spacers to properly fit them on the car? What size, and where do I buy them?

2. Would be looking to replace the ugly plain center caps that come with them with "IROC-Z" caps; will regular reproduction caps like these https://www.ebay.com/itm/1985-1987-C....c100505.m3226 fit, or do I have to use stickers on these wheels? The stickers seem to cost more than the actual caps on eBay (assuming I can use the caps).

3. I've never had a car with exposed lug nuts, and I don't want them to rust/look like crap a year from now (car will be parked outside). Where's a good place to buy a set of Black lug nuts that don't cost an arm and a leg?

 

Iroc replicas are all 0 offset, which is the same as the factory FRONT wheels, so you will NOT need spacers in the front. Fit is the same as factory. Factory REAR wheels have a 16mm (approx. .75" inch) offset, which makes the wheel tuck IN a little more than the front. The replicas, having "0" offset, will stick OUT about 16mm/ .75" farther than factory.

So to answer the question, no you do not need spacers at all. Front or back.

I was told factory caps would fit replica wheels. Never researched it, so I can't be sure.

My factory 88-90 style Iroc wheels use a lugnut with threads on the outside for decorative lug nut caps. I know those decorative caps were used through the years in various colors, on various GM cars. I had always assumed the 85-87 Iroc wheels used them as well, but double check to be sure. I know they come in silver too, although mine are black.

https://www.ebay.com/itm/IROC-TA-Bla...paBJnt&vxp=mtr

 

A couple of things:
Does adding the front rims to the rear make the track width equal (front and rear) or would it now be somewhat wider on the rear due to the offset? (Being wider would assume that the factory "correct" track is narrower on the rear due to the offset).
As for lug nuts, I went with McGard chrome lugs. No caps to deal with and in as much as the feedback I've received, unnoticeable. Of course being chrome, they aren't black.

 

I have no idea. I had always just assumed it was even, assuming the proper wheels. Meaning from the factory, the rear hubs were a hair wider than the front hubs. 16mm in fact. ...but I never measured, and I've never inquired, so really I have no idea!!!!!!

 

Good to know re: spacers.

And good thinking on the threaded lugs with the Black plastic caps! Will probably go that route as they've held up great on my other two cars.