Auto body repair & detailing: Blending new paint into old paint, dual action sander, scotch brite

Question
I recently bought a 03 S10 that had been rearended at one time  & didn't receive a quality repair, it has a bad tape line & looks like they did the finish sanding with 80 grit (not kidding).  I want to fix this spot which is below the tail light & a ding in the middle of the bed side over the wheel well & another dent above the wheel well on the other bed side. My question is should I fix the spots, then wet sand the rest of the clear coat on bed side (on both sides)& spray color on the repairs only and then clear the whole bed. Or since I'm repairing more than one area would I be better off to just use a dual action sander & sand the whole bed & repaint (color & clear). I have had 2 years of vocational autobody training over 12years ago,but do not work in the field so I'm not a total rookie, but I definitely need some guidance. Thank You for any advise

Answer
keep it small, wet sand the primer on the areas of repaired damage, stay away from the cab so you can blend the color out without mismatching the color at the cab. Use a grey scotch brite in the areas you want to blend the color so you don't see sand scratches through the clear. Using a DA and even very fine paper will run the risk of a cut through in the blend area. Bill