I am considering the removal of at least part of the rear bumper on a 1996 Mazda 626 ES cronos. I am getting water leaks into the trunk and some of the leak is coming through the bumper. This bumper has a panel that is held in place with six or so Phillips screws. I haven't been able to turn them out yet but I am using PB Blaster to get them to loosen first. The screw heads look vulnerable to stripping.

Will this panel separate from the bumper? If so, can I somehow seal the bumper so that water cannot gain entrance to the interior of the trunk.

I will try to get some pictures of the bumper to show what I am dealing with.