Maybe Conn only Westchester County N.Y. all consoles for Fire have 3 digit numbers,and they can vary based on the talk-group selected from the same console position. Transportation are 4 digit, and also vary bases on talkgroup. All mobiles, portables and bases on the system are 5 digit.
I already knew about the console RIDs being high numbers (60000s), but I found that the last two digits of the RID were unique to each troop. I also found that most troops had two consoles. (Troop H has four and Troop E has three from what I came up with) I wasn't able to log Troops A, G, or L.Each console position has its own ID for each talkgroup, typically in the 64xxx range IIRC. Basically infrastructure products in Motorola trunked systems are assigned high numbers. If you look at other moto systems in the state you'll see that pattern.