1996 Pontiac Grand Am dragging right front brake

I noticed my right front brake was dragging on the way home. When I got home the right front brake and wheel rim was indeed hot and smelled. So being I have the time, I put new dust boots on all four wheels and new piston seals on the front brakes. I cleaned out alot of muddy looking stuff in the calipers and wheel cylinders in the back. I figured the dirt was interfering with the piston returning to its state of rest. But, the problem still exists. I bled the brakes alot to remove all the old brake fluid. I kept everything clean and went buy the book. I also cleaned all the brake surfaces when done. The crome plating on the piston in the front brakes is in excelent condition. The car actually drove fine the first time I drove it but, the second time the right front brake was dragging again. The brakes work smooth and there is alot of brake pad thickness. I have not beed the system at the ABS modulater bleeders cause, I never let the amount of brke fluid go too low. Whats going on?