Gateway, your lean mixture symptoms are somewhat consistent with an intake air leak, though it should be lean at idle as well as at high speed, because the intake vacuum is highest when the throttle is nearly closed. Hence an engine with a leaking intake gasket is usually hard to start and will not idle. However it is possible that you have something else going on that compensates for the leakage, such as the choke is not opening properly when the engine is idling.
A continuously wet intake gasket obviously has something wrong with it, and the most likely thing wrong, is leakage. The intake pulsations are likely to cause fuel to be blown out, as well as air to be sucked in. While this might not be noticeable on a 4 stroke since the expelled petrol would evaporate on the suction part of the pressure pulses, on a mixed-fuel two stroke the oil will be left behind when the petrol evaporates, and the gasket will therefore be oily. That oil will also help to obstruct the leakage at idle and allow the engine to run.
Nearly all engines have an insulator between the carburetor and the intake pipe. The purpose of that is to keep the carburetor cool, mainly because cool intake air is denser than warm air, so a larger mass of air is able to enter the engine, giving higher power. Removing the carburetor insulator will reduce engine power, usually to a noticeable extent.
I suggest you look closely at the parts list and see of there is supposed to be a fairly thick plastic insulator between those two intake gaskets. It would be possible to use two gaskets together in the hope that it would work slightly as an insulator, but it would be backwoods engineering.
If your intake gasket gets wet while the engine is running, it is leaking and needs to be fixed.
