My '98 2720 also had the connector on the street side as mentioned by Trainguy.
Also as mentioned by Paul Heuvelhorst, the amplifier had to be turned off.
The basic setup is that the coax from the antenna is routed down through the support arm of the front shell and at the connector is hooked up to a coax dropping down from the amplified jack plate.
If the amplifier is only needed in some situations, it seems a Y could be placed prior to the ampilfier and another jack plate located in the camper. This would allow for hooking the TV up to a satellite or park cable by disconnecting the coupling outside and using the new jack plate. Otherwise, the antenna could be used from the factory supplied jack plate. Or just a second jack plate connected to a drop that would come out near the existing one for cable/satellite use.Just a thought.
Happy camping.