Basically you post a topic stating you would like to start a group build (like you kind of already did haha) then state the scope of it, what type of kits are allowable (is it scale specific, only aircraft, or all vehicles and figures from the period modeled, stuff like that) Once you see you have 5 or more people (not an arbitrary number) you go to building! We just got through a Battle of Midway GB late in the summer, I started that one as it is a big piece of history for me too. I think if you started one in a few months it would allow enough time for some of us die hard Pacific Theater Aircraft freaks to finish up some of the other GB's we're in... if you want to lead the one this year be my guest!
I for one would be in, if it started say on the first day of the attack, June 4.. or any day thereabouts or after (I'm up to my eyeballs in GB's right now). I'm not sure what I would be building, I do have a few SBD's in the closet, but a torpedo carrying B-26 might be fun to attempt as well! Let us know! Just make a new post titled "Battle of Midway GB" when you are ready, and maybe with a start and end date in the title.. actually we never "officially" ended the one last year so you could just do a continuation!
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oh yeah make sure you start the thread far enough in advance so some of us can get in there and start chatting about it and maybe get some people thinking about joining!!