Trailer wiring info

Hi. I'm looking for tail light wiring information for a 1998 Malibu. I am
trying to wire up a 4 pin trailer plug. I don't have any service manuals
for this car yet, but I would like to find a diagram online that shows how
to wire this plug into the tail lights. Either that or info from someone on
the newsgroup that has done this before, and that possibly can tell me which
color wire is for what. I tried a few google searches, but came up with
nothing.

If I had the time, I would go out with a test light and figure out the wires
for myself. By the time I get off work, I only have about 3 hours of
daylight to work on the car, plus a wife and 8 month old child that want my
attention.

BTW, I'm not sure if those 4 pin harnesses are usually color coded or not,
but if it is, that would make the job a whole lot easier. The last one I
installed on my Ranger was the plug in type that required no splicing.

Thanks for any help in advance.
Sharky