I say put them all in, and not worry about it. Zone 2 isn't as large as Zone 1 so all the talkgroups will be able to fit into one system. What I do is is, I make up one system for OPP/MNR/EMS with just the control channels for Zone 2, then make up a separate system with all the same frequencies and use it for for MTO only and put it on Scan Mode
Or i'll just put in the control frequencies in seperate systems for each tower, and put all talkgroups into each system and put it on Search mode, Either way works. Again, there's lots of space to put all zone 2 talkgroups into one system so I would do that and not worry about it. Nothing much ever changes really out in Zone 2 anyways.