How to change the headlight on passenger side of

Well, forgive the generic response.. I have done loads of Honda... but not a 2003 Civic...So, here we go..

Open hood. Locate top headline tab. Remove screw that secures tab.
Next, locate nut on backside of headlight assembly - remove it (it should be a round fastener that has a hex nut top.
Headlight should pull away from chassis.
Connecting cable has a lock tab that must be pressed. If you just pull out on the cable assembly - a large, round (2.5 to 3 inches in diameter) water proofing shroud will come out of the headlight assembly - bulb and all. You will still need to remove the cable connector from this assembly.

Install a new headlight assembly in the reverse manner.