Ok I am going to ASSUME you are comfortable working with COLD (not energized) electrical circuits.
Step one turn it off Unplug from shore. kill generator
Now if there is an inline fuse JUST to the inverter. Pull it. or disconnect 12 volt lead.
Open the 120 volt junction box. Identify the IN and OUT wires and using a sharpie or other marker write IN and OUT on the wires.. Disconnect them from the INverter.
Using any good method (I really do not like wire nuts but they are the easiest
Connect the IN to the OUT.
White to White
Black to Black
and Bare/Green to Bare/Green
Tape all connections to insure safety and security.
YOU NOW have no inverter
Remove inverter to repair shop (NOTE that joining of the Romex really shoudl be done in a nunction box.. Any hardware).
This also assumes you have a sub panel. IF YOU DO NOT get one and run IN to the IN and breakers to the branch outs.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times