Pretty easy to install -- I recommend powering-off your T500 wheel and removing the actual wheel (which takes maybe 3 minutes), as shown in the first half of this video:
Link: https://www.youtube.com/watch?v=I7cKX6F1ah0
Then, using the enclosed hex key, remove the 6 hex-head bolts around the "GT" center -- once the bolts are removed, you can easily lift the collar that holds the 6 bolts and remove the GT center. Place the new BWC-T500 center in place along with the collar that holds the bolts, then re-install the bolts. Note that there are 3 long bolts, and 3 short bolts.
The 3 long bolts install at the 3 o'clock, 11 o'clock, and 1 o'clock positions (these hold the wheel to the screw-on "quick disconnect" on the rear of the wheel, so you MUST put the long bolts back in the correct positions). Then install the 3 short bolts in the 12 o'clock, 5 o'clock, and 7 o'clock positions. Just insert the bolts and start them initially -- don't tighten any of them down fully until all 6 of the bolts are stated. This will ensure proper alignment of the collar, and it will also help prevent any of the bolts from binding.
Once the new wheel center is in place and all 6 bolts are properly installed and tightened, re-attach your GT wheel to the T500 base as shown in the second half of the video link above.
Now go racing and enjoy your new bling!
I took the attached pictures for the Website -- I still need to complete the installation instructions to be included with the wheel centers, but that should be done in the next day or so. Once I get that done, I will update the Bodin Solutions Website, so keep your eyes peeled. Most likely, you'll be able to place an order by Wednesday of this week.