Side Mission : Seems Simple Enough
See Alma in the warehouse- she'll give you a sharp little speech and tell you to go retrieve a truck from the bayou. Always the bayou.
Like the other sidemissions, find the site, and wipe out the opposition. This is slightly more important for Alma's missions because sometimes you'll need to hitch the truck up to the trailer- you can't just grab the vehicle and vamoose. Once you are set, it's time for the long slog bag to civilization. Watch out for some of the rougher roads, and don't trust the minimap too much- a lot of the turns have a rounded corners, rather than the sharp angle the map shows.
Play it safe, and soon you'll back with Alma, ready to do this again and again.