Very odd. I see that it's a stock 98 too. Did the stock bumper fit fine?
I've assembled and disassembled the kouki bumper on a 98 many times, and I have never seen it fit this way. The 6 bolts that secure onto the support should've taken care of the problem, but the way the bumper curves, it looks as if that support is bent somehow.
Did you install the side metal supports that attach to the bottom side of the front fenders? it's secured by a plastic tap and screw w/ a 10mm bolt head.
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