Yes… You should always cover any areas you don’t want coated. Over spray will occur, just like any spray paint application.
While our General Application (products other than the polyurea cartridge kits) cure more slowly than automotive paint dries, cleanup would otherwise be required. It’s advised to avoid the need for cleaning over spray if possible.
See our truck bed tape & cover directions on our Spray-lining.net support site for a printable set of instructions.