It might be as simple as dissolving it into a specific amount of Everclear and then dosing the liquid.
(i.e. 100 mg winny into 2 ml of EC = 50 mg/ml, so take 1 ml)
This is done with other things, but I don't know if it's done with winny -- I'd hold out for an answer from somebody that's done it, you might be able to find it through a search too (I'm sure it's been discussed before)...