Well, you don't "need" the EGR. You'll need to tune it out if you do not want codes. There is some fabrication involved if you want to retain EGR. Basically, it would require a divorced EGR mount like the Gen-III trucks used to have, and a custom braket and plumbing modifications to work. Mine's like that and works flawlessly.
1998 C2500 Suburban LT: GM Crate 502/Brodix Heads/234-244cam/4L80-E/3400 TC/Gear Vendors/4.56:1 Eaton/Dual 3" and Ceramic Headers
1999 C1500 Tahoe LT