New to the site and having just done a detail and wax for the fall, I noticed that there was a ton of debris in the back around the taillight housing. After youtube showed me now to remove them, not easy as all but was surprised how much junk was built up behind them. Would be a real nice spot to have rust and rubber break down in the future if not cleaned out regularly.
Spray WD-40 behind the plastic after every wash to displace the water & keeps the metal slippery reducing dust/dirt build up. Pine needles/tree debris=shop vac/old toothbrush. I have many customers w/tree debris so I give all the rain gutters the same treatment & flush the fender drains w/smooth bore nozzle. The rain drains are @ the top of doors behind weather strip, WD-40 them too & weather strip. No stink or interior dampness.