I have both pieces- I could sell you one or both. They are simply bolted to the bumper and valance with 10mm head nuts.
I believe there's a rivet located between the the fender flare and bumper flare that needs to be drilled.
The '97 Limited, '99 SR5, and '02 Limited I have taken off have all been the same- as far as attachment method. They attach with 3 or 4 studs/nuts. The studs at the top are secured to plastic brackets that rivet to the flare pieces, but there is no reason to remove the rivets [emoji1360]
I have both pieces- I could sell you one or both. They are simply bolted to the bumper and valance with 10mm head nuts.