I suppose someone could spend the two bucks on a bottle and test it on a scrap piece of lexan. You can also buy methanol in bulk at places that sell racing fuel. I don't know how pure that is but it runs about $4 a gallon. I'm thinking that methanol is extremely hygroscopic and as soon as it hits ambient atmosphere your 99.8% diminishes rapidly. I'm no chemist so someoneplease step up and let me know if I'm wrong about that.

Found this on Amazon.com 99.85% slightly less than a liter for 10 bucks.
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