Depends on the extent of the rot.
If it is rotten under the walls odds are good it will need to come out and the walls removed.
Pull up the carpet and check it out use a scratch awl or grind down a broken screw driver.
Poke the floor wood at the wall in several places if the point goes in easy you have a problem.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
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