the plug isn't gonna do much. i mean, it should be better than stock, but it ain't gonna suddenly boost you up a hill or blow away cars off the line.
i read your other post, and i think you should buy that dremel before spending money on other products. if you get a fancy carb but don't open up the intake manifold port, it won't be able to breathe like it should.
another thing you need to understand, is adding a pipe, carb, etc but not changing the gearing won't make you go much faster, top speed-wise. you'll get up to speed faster, but then you'll be winding out your motor, and still going around the same speed as before.
once you get the motor hopped up, then you can go to a smaller sprocket, still get the acceleration and hill climbing, and a faster top speed.
the biggest problem you mentioned is you don't have a lot of money or tools. unless you can find a rich mechanic chick to marry, you're kinda stuck...
