Scott,
I'm not 100%, but i think the SHO and the 5.0L share the same injector body. If so, Autozone has a set of o-rings(pn/ 800-9212) for $4.99. Thats a set of 16 o-rings. When they looked up the o-ring and also injectors for the SHO, both said N/A. If you know Autozone, it does'nt mean that...