Less than 15 minutes per turn signal
1) You may want to jack the front end of the car up with a floor jack on proper jacking points. It isn't required though.
2) Look up under the bumper where the turn signal sits. You may want to use a mirror if you can't get under the front end.
3) Twist the bulb holder Anti-Clockwise and remove it from the lens.
4) Using the wrench or socket, un-do the 2 "cheapo" sheetmetal nuts which hold the turn signal housing to the bumper.
5) Pull the turn signal housing out from the bumper.
Assemble in reverse order.