If you don't need the transfer switch you can bypass it by splicing the shore input wiring to the load (panel) wiring.
10 pcs 6 AWG 6 Gauge Butt Splice Connector Pure Copper Tin Coated Marine Grade Uninsulated - by WindyNation
https://a.co/d/0oo4ib8
If you boondock and think you may use an inverter and run off the batteries, maybe a manual transfer switch.
APIELE Changeover Selector Switch Box 63A 3 Position 12 Terminals Poles 440V 3 Phase Universal Rotary Cam Selector
https://a.co/d/auLBXXW
If you want another ATS, I just bought and installed this one. Pretty happy with it so far.
Go Power! TS-50 50 Amp Automatic Transfer Switch
https://a.co/d/dd49sbM
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