Gen prep should also include a transfer switch that has cables from the shore power inlet and generator on the supply side and the coach on the output side. I have a hardwired EMS wired in between the 50 amp power cable connection And the transfer switch. The EMS doesn’t like my Honda generators (2x eu2000s) so I wired a new 50 amp plug up front to plug them into, this bypasses the sensitive EMS and works perfectly. I did remove the gen prep propane feed line just to get it out of the way and to avoid any possible damage to it in the future.