I didn't think anyone cared, lol I also own a Lightning and thats where I got the idea from. You have to remove the plastic cover on top of the engine to expose the S/C, the bypass valve is on the front of the engine on the drivers side. What happens is the valve is normally open and when you get on the throttle it closes. If the valve is not set correctly it will hit the stop before it gets closed and leave the valve open and you arn't getting full boost. Go to this site and see how to set it on the L, its the same style Eaton S/C. Be careful and dont leave the lever off the stop or the valve can stick closed and it will not idle good at all if this happens. If you do not understand the directions on this site let me know and I will help, scroll down until you see Boost Act Adjustment. Its right after the pulley's. Hey I swear this works. Mine was way out of adjustment. You can see where the bolts make a mark on the plat and where you end up is how far it was off.
http://home.midsouth.rr.com/lightningpage/tips.html