'69 Chevy Step Van

I am looking at buying a '69 Step Van but I don't know much about them or where to find information. Does anyone know of a place? I am also looking to chage the rear end so that it idles around 70mph in third gear. what kind do I need? Right now it tops out at about 55mph. Thanks for any help.

ebay often has older Haynes and Chilton manuals. I just got one for a 76 Dodge Aspen. How cool is that. As for the rear end, what gears are in there now? You are probably going to need a gear set for a car not the heavy duty/high torque unit you have. Good Luck.

I don't know what gears ar ein it now but I would guess low 4s