Right so the 98 will have the double 90 intake.the 99 will have the better intake
Android Fire
From 98 to 99 the visibile changes are pretty well covered above, so I'll add a couple of the standard manufacturing ones as well to make myself look good.
Maybe wheel changes
Maybe a couple different colors
Airbox
Coolant bottle
Maf sensor/TB
Behind the scenes though, there's tuning differences in the PCM. There are BCM and some sutle wiring/circuit differences where they found needs to upgrade/redesign.