I believe they pulled most of their VHF out of the cars.
For Fire/EMS Interop here we put up VHF & UHF repeaters on the East and West side of the county and then gave users in other counties permission to use them. When a dispatcher requests units from a neighboring county they ask them to switch to the repeater and the repeater is patched to the Tac TG being used for the incident. If our units go into a neighboring county the dispatcher can patch a Tac TG to a neighboring county channel with a base radio that the dispatcher can change channels on. For interop with Madison Co, we have used Interop 4 several times.
For Law Enforcement interop, it is usually dispatcher to dispatcher.although we do have the ability to patch the old State Net (155.010) to a law enforcement TG if needed.