My 98 had electronic ignition problems where I replaced the module twice in 10 years. It would sporadically cut in and out at different rpms and the last time I thought it was a carburetor issue. If you want to take the gas out it is easy as all you need to do is disconnect the hose at the carburetor and put it in a gas can and then jumper the fuel pump and it will drain rather quickly. The fuel pump could be an issue also and if it hasn't ever been replaced it would be time. The gas filter is a strange character as it is hard to tell when to replace it but a clogged filter would affect the engine more at high fuel flow (WOT) than at idle.

Now if I could get my hands on a replacement Airguide speedometer everything would be perfect.