The fuse is intended to protect the wire. So if references say to use 60 amp, that is the most you should use. No problem using 50 amps, as long as the wire will not need to carry more.
Does it feed an inverter? What is the capacity of your converter? If either are more than 50 amps, go with 60.
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2002 Classic 30 Slideout -S/OS #004
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