This is a vehicle side mission which is started by entering a vehicle rather than going to a phone. It is recommened you do these missions to help build up your score.
Go to the Porka in southwest Kings to begin. A guy named Jimmy needs a driver, so you must pick up a new car in south Brocklyn Docks. After getting in the Taxi, you must go pick up Jimmy at the National Reserve Bank in south Ardler. Once you pick him up, you will receive a four-star wanted level and be told to go to Bubby's place in northwest Kings. Dropping him off, you will then be told that a hitman has entered town and that you must get rid of him by rigging a car with a bomb. Know that you do NOT need to rig a car with a bomb, but instead blow it up by simply shooting it. Doing this will complete the mission.
(Must have gun.)
W, big S, big W, follow N, small W, small S.
Follow W to Taxi.
E follow N, small E, big N, small E, big N follow E, N when hear bell.
S, big E, S road just before cops, E.
N, big E to end, big N.
Block car and shoot to explode. END!
Video Strategy (External Link)
If the directions were confusing, here is the video: