Racincuda is on it! Yes those throttle shaft bushings come in the trick-kits and a few others..Supposedly they are a teflon bushing....Basically you take off the throttle plates, pull the shaft out and see what's left of those bushings first , the shaft will have a recess for them to ride in{one on each side}..The new bushings come narrow and thick, wrap them around the shaft and slide it back in...It will be hard to get them in the bores,but after you do just work the shaft back and forth and put side pressure on the shaft to side load the pressure...Those bushings will flatten out and work themselves the whole way around the throttle shaft{I do one at a time}...Just work it until the shaft moves freely...This will work well if it is reasonably within tolerences....If the shaft or bore is too far gone , it's new bushing or bottom end.....