RE: Stuck carb screws
You might try using the Dremel cutting disc to cut a slot in the screw head, heat the thing and then try unscrewing it. If the carb barrel is steel it might be rusted enough to be stuck. I've soked stuck carbs in Evapo-Rust non toxic/fumeless rust remover (available at AutoZone) and loosened them up. Might loosen rusty screws too.
Terry in LP