A 98 bumper is the same as yours, it will fit as a direct replacement. EK civics front ends were updated in 99, if you want a 99-00' year front bumper you will have to change the hood, lights, bumper, grille, and fenders to the updated pieces.
A writeup on how to do it. http://www.jdmuniverse.com/forums/view.php?pg=ekconversion