Historical Textbook rewrite

Hello- We're a nonprofit, all volunteer US Marine Corps history organization. We are endorsed by the USMC Force Recon Assn, and are in the process of petitioning the endorsement of the US Marine Corps History Division. However, in order to accomplish that goal we need a little help. We have a textbook that we're trying to create for new members. I have a significant amount of information, (270+ MS Word Pages) but it's been written by multiple contributors. There are major tense problems, some wrote in first person, others in third, as well as duplicate information. I'd like to work with a CW who could handle writing a few more sections from notes, and editing the existing information. Correct English grammar is mandatory. The time line is not a rush. We're looking to go to press in April 08.