The hoods have different dimensions. Specifically, the new HDs hoods have a much longer plastic cowl fairing (the big plastic part just in front of the windshield is NOT a part of the hood!) that would leave you with several inches of open engine that affects under-hood airflow and leaves you with about a 6" open gap between your hood and the windshield. The latches, lift-arms and pivot points are also in different locations. The power-dome curve in the front is the full width of the hood and will leave you with a noticeable (and ugly) gap between your hood and front quarter panels. Finally, the new HDs have a flat nose and the hood matches that, whereas Suburbans up to 2000 had the same, slightly apex nose of Chevrolet full-size trucks from the '90s.
Bottom line, rather than try and get a stock hood for a truck that is designed completely different, check online and see what cool aftermarket hoods you can find for your Suburban. They will be cheaper to get and you'll ultimately be happier with the outcome.
