Modern Vespa

I have a Nero Graphite '06 LX50 with ~5700 miles, that currently does not run and I have no more time (or money for that matter) to try and figure out the problem, I have spark, gas and compression. New battery, CDI, and spark plug.
It stopped working about 3 months ago when I was riding down the road and then just quit at a red light and never started again. I noticed that I had no spark, so I replaced and still no spark so I replaced the CDI(3 months later), got spark but no go power. I know the gas is old and most likely useless. But I don't know how to drop the gas tank and drain it let alone properly remove the carb. Please let me know anything that may possibly help solve my problem!!!!!! Could it just be old gas and a clogged carb? It still sounds like it wants to turn over but it just won't. Any help is much appreciated.

Thanks for your time,
Brett

Is it a two stroke? I have a 05 Typhoon, and all I do, is to take the carb loose and take off the bottom of the carb, and clean it with carb cleaner, taking out the jets and spraying them and the little holes in them.....
You can get the carb loose, by the access hole in the bottom of the pet carrier.....
I would use some starter fluid, and spray it in the engine, before putting it back together....
The old gas, can be drained under the gas tank, replace the clamp, with a worm style one, that you tighten with a screwdriver.......