Re: A project I have in mind...(but I need a little help)
You might want to check out the 1910 Pierce Clone and the 1912 BSA Copy in the DIY Home Built section. Fishguts may be right, you might want to start with something more simple. The Marsh has what is called a keystone frame where the motor is part of the frame. I don't know of any modern motor that would do this. As for the tank, make it yourself! It looks pretty simple as well as the forks. I feel this is what this site is all about, making your own unique motor bike and making it functional. And doing it yourself makes it all your own. The Marsh would be a good choice , but I'm not so sure it would be as simple as you think, good luck and keep us posted.
Modern Antique Cycle