Rob
The 98-99 trucks can take the later Sport lites, but you gotta do a little hackin' an a hewin' at the radiator support/headlight area... The bigger issue is a harness... there are a few different ways to approach that... They are brighter, really brighter if you wire both beams to come on at the same time... The Sport lights that are available from time to time seem to be OEM. . this is from other members that have been able to pick them up...
Colin