you have to pull off the cowl first, its got a few screws in it, i think 2 under the rubber seal between the cowl and the hood and then 5 or so on top of the cowl. 1 in the opening and 2 close to the wipers and a few across the top of the cowl. pull the wipers off, pull out the screws then pull out the cowl. look for a lot of crap all under that panel that you just pulled out. remove crap and flush it with water.
this is the cowl--not my pic btw and it is not the same design as our cowls, so just use it for reference of what a cowl is, its the whole panel there.
Jeep wrangler cowl image by runit3 on Photobucket
hopefully someone who is more helpful will chime in