If its Wood County I see they are licensed for 110watts ERP on their Fire KQH447 /WPQY958 FCC licenses. They also also licensed for repeater operation on 153.890 and I see Hoytville has 151.880 simplex (non repeated).
Kenwood TK7160 mobiles run in flavors of 25-50watts power output , with a 3db gain antenna they should be putting out close to 80-90watts.The topography map appears to be mostly flat land is that so?
Narrowbanding does lose some range,but it should be nominal.In
VHF we are finding sometimes its not just changing the channels from wide 25khz to narrowband 12.5khz that is the only requirement,some radios need to tweaked aka re-tuned to optimize operation in 12.5 bandwidths.
As PC Comms mentioned there are vehicle repeaters from Pyramid Corp available but I can tell you they are not cheap as inband notch filters add to the price a bit
pyramidcomm - Vehicular Repeaters Products
I also see a license that was for Hoytville-Jackson Twshp KNGK203 that expired in 2003 for 153.890..you could try to get re-licensed for that for an input frequency into a vehicle repeater system.
Most vehicle repeaters go into your First Due apparatus or even a Chiefs vehicle,if space allows.
Wish I could recommend a more cost effective unit by Vertex called VX1000 but the
VHF model is not narrowband complaint now
Land Mobile Radio | Vertex Standard | VXR-1000
But then again, I am going off of infos in your profile as to your location and agency.