Don't bother replacing the lower part of the bumper with the plastic c**p.
It's just going to get broken off again when you go wheelin'.
You might as well put on a good aftermarket bumper that will accept a winch and lights (if it's the front), or a swing away gas can (if it's the rear).

It'll really toughin' up the look of your gen 3 too.

Good Luck

'02 Montero: OME suspension, ARB front bumper, homemade skid plates & spare tire Blitz can mount, extended diff. breather, K&N air filter, Optima Yellow Top, BajaRack, IPF lights, Goodyear Duratrac 265/75/16's, RUD 4x4 Grip chains