The grille fastens down to the top of the top support. The lower mounts you pictured should fit in the lower support snug . I usually need to use a clip pliers to pop the grill up out of the lower holes. The upper support should be on the grille whole setting the grille in place . Install the headlight rims and then the outer bolts on the upper support. The lower holes have side to side play so you can move the grill side to side to line up the headlight rims and center the grille..
If your upper support is lifting the grille bend the ends of the upper support up so it holds down on the grille. When the grille is installed with no headlight rims as pictured below you should be able to move it side to side to install the rims. That is why movement is in the upper and lower fasteners and upper support holes are slotted
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