Hub rings are extremely easy to install, so easy that the point of this how to is really just to show some pictures of the installation as requested by email.

When do you need hub rings?  The GTO has an odd bolt pattern so it turns out that most after-market rims with the right bolt pattern are actually meant for BMW's.  The problem is BMW's use a larger hub.  In order to make sure rims fit tightly on the hub a hub ring is used to fill the gap.

Where do I get hub rings?  A lot rims come with hub rings if you tell the rim supplier the application when you order.  They tend to be cheap plastic ones.  I bought the hub rings in this how to from CsiJason on ls1gto.com.

1) Remove the rims/tires.  It's likely that the hubs will be rusted.

2) The hub rings have tight tolerances so the hubs need to be cleaned and sanded.  It's best to use emery cloth.

3) Once the hub is completely clean I applied a layer of anti-seize.  It's brown so it almost looks like rust in this picture.

4) Finally slid the hub ring on.  At this point the hub should be the right size to fit the after-market rim perfectly.