That is a tough decision. How many miles on the '96? Is the H1 your daily driver? Don't know if I could stomach selling the '96 after putting that much money into it.
On another note, if you are in Des Moines, let me know if you find any good places to wheel around there. I've been going to check out MIOBI
http://miobi.org/forum/index.php but have not had time to get over there yet. Not sure if there are enough obstacles to keep a Hummer happy for very long.