converting to a 03-06 front end

To change a 01 GMC front end to the 03-06 front ends do you have to change anything like the bumper brackets, or will it just bolt up?

You have to change the front fame horn plates to the newer bumper brakets also the side supports. also the the grill will inter change without a problem

Thanks for the help

were you able to install bumper yet? I went and bought the grille and bumper this past weekend and the guy that sold them to be told me it needed a bumper bracket, which i knew but he told me it came in 6 pieces. does this sound right?