How to rodent proof a trailer?

My new -to- me cat trailer came with an estimated 10,000 acorns inside the frame. Any good ways to keep the critters out, and allow water to escape? The tongue, frame and cross bar are closed sections. Sealing isn't really an option with all the bolt holes. The critters and or dog chasing the critters damaged wires on my utility trailer. Thanks.

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John

Nacra 5.0
CT
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Stainless Steel scouring pads...cheap!

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Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
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