I the o-rings have shrunk, the needles will screw themselves in or out - rarely if ever do they leak air. Try driving the truck around with the glow driver attached. If the engine doesn't quit with the driver attached, the needles are still too rich. Also keep in mind - the idle needle controls fuel mixture up to about 60-70% throttle travel and while the main needle controls fuel mixture above that, it controls overall fuel flow too. If the main needle is too lean, it will interfere with the idle needle. Generally you set the main needle (high speed) first and set the idle mixture second, but only when the idle needle is "in the ballpark". If the idle is way too rich, often you will get too lean on the high side. It would also be a good idea to ensure the idle gap isn't too large. Many manuals spec a 1mm gap and 99% of the time that's way too big. .5-.6mm is a good starting point. Make sure the throttle linkage doesn't bind at all and the throttle closes against the throttle stop easily and quickly when the trigger is released to the neutral position.