A safer way to connect the inverter is to wire it to an outlet (in an outlet box) and then plug the RV's cord into that outlet as if it were shore power.
Just make sure that you turn off the circuit breaker for the converter before turning on, and connecting to the inverter. You don't want the converter taking power from the inverter and trying to pump it back into the batteries. That loop will drain the batteries rather quickly.
Once, I forgot to turn off the converter. To avoid having that happen again, I connected the coil of a normally closed relay to the inverter output, and ran the AC power to the converter through the relay contacts. Now, turning on the inverter automatically turns off the converter.
2011 Silverado 2500HD Duramax, 4x4, crew cab, long bed
Palomino Puma 253-FBS, 27' 5th wheel
1994 19' Class B on Chevy chassis