Keyless Remote Rebuild Kit Is It Possible To Avoid Dealer Diagnostics And Program A New Remote Keyless Entry For 2003 Park Avenue Myself?

Is it possible to avoid dealer diagnostics and program a new remote keyless entry for 2003 Park Avenue myself? - keyless remote rebuild kit

A claims service Buick dealer service a new remote keyless entry on my 2003 Park Ave (Ultra not presented) must be in his tent, and programmed with its system of diagnosis. I had so many bad experiences with dealers that I have a hybrid skeptic. Can anyone tell me whether it is possible to my new keyless entry program itself with the correct instructions? I was told that it is possible with certain brands and models.