Snickster posted the kit that comes with the external and internal antennas. However, It comes with an omni-directional antenna for both exterior and interior.
IMO it seems an omni-directional antenna would (both in and outside) would be more useful if you are "on-the-go" frequently. With a 40' coach I'm sure the standard internal omni-directional antenna would give you good service.
Wilson does make a different kit for "home" use that comes with a directional antenna. It's called the 4G-X Connect instead of the Drive model. Here is the link to the directional antenna that it comes with. http://www.wilsonamplifiers.com/wilson-yagi-directional-antenna-wide-band-50ohm-n-connector-314411/
I don't see why you couldn't use that with your setup provided it has the same connector.
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