Where you are, a wet noodle should get you into the repeaters in the Wasatch from a big part of the state, so I would not sweat minor issues with antenna efficiency.
I use a trunk-lip mount on my hood, with the antenna directly opposite the broadcast antenna on the other cowling. For 'around town' use, I have a 1/4 wave whip that goes in and out of parking garages with no trouble, and would probably work well for you most of the time, too. I have a 5/8 wave and a taller antenna - I think it's 5/8 over a 1/2 wave - that I use on the open road. I prefer not to use the tallest antenna, though - it puts quite a bit of bending force on the hood. The shorter ones are no worry.
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