you will have to remove the two mounting bolts and pull the reservoir out a bit if you want to take the cap off and check the coolant level in it. I would much prefer another semi-transparent plastic container that is easy to visually check, like the one in the RIPP kit.
You do not need to remove the reservoir to check fluid level. You can just remove the center cover between the grille and the bumper. This will allow access to view fluid level and top off as necessary. Do you have a pic of the Ripp plastic container? i would like to see it...