Yes, definately a 3+ hour job on the contour if you have never done it before. Get your motorcraft rebuilt alternator from
http://www.fordpartsonline.com/ If they only want $170 for the install, like PA 3L said, get it in writing!!! For that price, I am not sure if you want to do it yourself, unless you have a nice size toolkit, and access to a lift. Search around for some very recent alternator threads, and PM me if you need help... -Nick