MARCS and Summit Co Regional are Moto 800/900. Just program them in with their possible control channels and you should be good to go.
If you want to receive ICALLS, add a Private Wildcard talkgroup. You have the choices of Group and Private for wildcards. Group will let you hear all talkgroups, even those you don't specifically have programmed in. Private will let you hear ICALLS if the system uses them.
If you're doing this manually via the keypad:
1. Create a new talkgroup - associate it with the scanlist you want it in and the system (TSYS), and:
ID: Wildcard
Type: Private
Mike