So i've been away to Europe for grad school for the past 13 months and will be returning to my car next week (finally!).

I usually run a about a 66% meth to water mix in about a 4 gal tank. Prior to storing the car I filled the tank with this mixture. Does anyone know how well meth stores long term like this?

I'm not home yet so I do not know the current level in the tank to see if there has been any evaporation over the 13 months. If there has, is there any way to measure the current meth content?

Draining and refilling the tank would be a nightmare.

any help/experience in this area would be appreciated!

Oh yeah, anyone know of a cheap place to get meth in upstate NY/Mass area?