There are a number of good examples of doing the forward hatch replacement on a 27. I really needed to do mine, so I did a little video with commentary throughout the project. I didnt have a handy cameraman so I could not show me doing the work. Hope you all enjoy.

Pretty easy job. I highly recommend it. Very satisfying without too much work.

http://www.youtube.com/playlist?list=PL3u9rWfIEUeBgBUvikmqF814vXzWsWZm0