Defo try it after you dehydrate them! 

Steep them in alcohol for 8 weeks and then do a hot water extraction by gently heating the same mushrooms in water until about half of the water has evaporated. Then you combine the alcohol tincture with the hot water extraction to make the final tincture. 

Doing both processes makes sure you get the full range of medicine out of the mushrooms (some of the properties are water soluble and some can only be extracted with alcohol)