Hi. My name is Chris and am also planing a 906 replica. Take a look at www.gunnaracing.com . They have just restored a 906 and have ALL the reference pics you could want in there 'PROJECTS' section.
If anyone has ANY tech drawing of blueprint ref, however rough or small, I would be hugely appreciative if anyone could send me a scan etc. Dont loose faith and be intimidated by the detailing. Start the project and the rest will happen.
I looked into making a Porsche 906 replica a while back, I was just about to have computer 3D models made up to then convert to CAD for machining. Couldnt find any kits when I was looking about 12 months ago...