[A/S] Truck bedliner

[WBCCI29072@xxxxxxx]

after only about 4years of shopping.
We bought a 2001 GMC Duramax, 47,000 miles, 2WD locking diff, it is sitting 
in the garage, just had the BrakeSmart installed. Cap arrives in one week.
 I also am thinking about a transferflow crossbed fuel tank.
Curious, it has a GM plastic bedliner. I'm thinking that's a great way to 
trap moisture and rust the bed? would that be an issue with a cap? should I 
remove the bedliner, and perhaps get a spray on bedliner?
Dan