Any recommendations on floor covers that actually cover all the way in the back toward the cab? truly custom covers that cover all the carpet?

[Inspectorcallahan]

Thanks in advance for any recs to check out

 

[BlueHemi1500]

I have the factory rubber floor mats front and back. My truck has the rear underseat storage option. They have ridges on the outside perimeters and do a great job at containing junk and minor amounts of liquids. These rear mats do not cover all the way to the rear wall as you asked, they are highly functional, with the rear underseat storage from my one year of ownership.
Another solution that I have used previously is carpet remnants they can be very cheap, and colors and textures. Carpet/flooring centers can be a great source. Depending on the carpet, they can be cut with a very sharp/new razor blade utility knife to custom fit.

BlueHemi1500

 

[Brutal_HO]

Look at Truxedo.