You have 9006 as the LOW beam, 9005 as the HIGH beam and unless you have a Xtreme, the fog lights are 9005. The 9045 is a dealer item (only 45 watts instead of 55 watts for a halogen lamp). You want HID's then use 9006 low/9005 fog&high. The sylvania.com site is WRONG. If you have a Xtreme, it's a H11 or H3 but only that model. If you want to be sure, take the lamp out, go to a autoparts store and compare it side by side with a new lamp.
Just my opinion on the matter.
2004 Colorado Z71 2WD CrewCab/I5-Auto/265-75-15 stock tires/rims
AWS Bug shield&vent visors/HID's Lows and Fogs/FlipBak cover/Depo LED taillights/Red Top battery