I would like to suggest you go and check the vents for the fridge, water heater and the furnace for the same deal.
Look carefully in the vent tubes and anyplace you think they could crawl into.
Might not hurt to look at the vent for the stove hood and the plumbing vent caps on top.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
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