Build over ice in an old fashioned glass. Squeeze lime, if desired.
Rye's spiciness probably holds up better than the Canadian, but the latter works better for the name... The Spruce Beer I used (and the first one I've ever seen/heard of) is from Empire Bottling Works.
Found a bottle of Spruce Beer at the gourmet soda store, and upon tasting it, I immediately wanted to mix it with booze. Drawing inspiration from Zach's Dark Phoenix, this is what I came up with.