Okay, here we go.
Here are the components you'll need: a set of front shocks, the coilover sleeves, a set of springs (these are 12-inch long, 2.5-ID QA1s), the machined top mount and a set of Torrington bearings. The Torrington bearings aren't necessary, but they do make it much easier to tighten the coilovers. For what they cost they're definitely worth it.
The top mount is the only real snag in this project. On the left of this picture is the top mount that came with the Bilstein coilover sleeve. On the right is the top mount from the group purchase a year or so back that's machined to fit our existing spring/shock top mount.
The coilover sleeve (part number at summit racing is BSN-B4BOA0000117) mounts to the shock exactly as our lower spring mount does. However, the outer diameter of the shock body is really critical. This Bilstein shock body measured 1.975 inches, and the mounting ridge is 2.100 inches. The ID of the sleeve is 2.00 inches. A very little slop in the size of the shock body can make a lot of trouble here. Example: whatever the donor shocks are for the Konis on my SC measured 1.920 in diameter. While .08 inch doesn't sound like much, remember that the mounting ridge is only 1.00 inch! So now you're counting on .01 inch of contact per side between the sleeve and the mounting ridge. How brave are you?
But here's how it looks when installed.
I loaned my racing scales to a friend this weekend, so I wasn't able to measure the difference in weight between a stock set of springs and the smaller coilover springs. I'm guessing perhaps 7.5-10 pounds, something like that. Hypercoil has a new OBD spring that's designed for lighter weight that might be a good option. This installation is shown on my LX because I had to harvest the top mounts from that car. This year I plan to try autocrossing the SC with this coilover setup and as I do so I'll update how effective this setup is. The first event of the year is a National Tour on 2/23, so I'll report on that. Any questions?