Javascript code Modification for an Ad Network

We need to modify a customized Javascript code. The modification shouldn't take more than 2 hours, since the code was written to make these modifications easy and fast. We won't provide FTP access to the site. We will send the JS code instead and after the modification is completed, we will test it in our side. The ad code works just fine, but we want to change the way that "ad views" are counted, instead of counting the view the second the ad code is loaded, we want to count the view once the "banner" is fully loaded. We will provide further information to the project winner. PLEASE: ONLY SERIOUS CODERS. WE NEED THIS COMPLETED BY TODAY.