A quick question about bumpers

Can Tru-flex bumpers (fiberglass with flex agent added) be mated to the fiberglass or should the bumper be rigid like the body? Does anyone recommend the procedure shown here?:


The Mar-Glass reinforced resin was mixed with its hardener, and then knifed onto the flange of both the body and cover.
Rivetteman2008-10-28 20:01:34

The fiberglass is not as forgiving in movement and will crack, you can use urathane bumper adhesive/filler in between the bumper and the body then use as a filler on top and block sand.