I searched around and found a place you can get the wiring diagrams and repair information you need. It also covers all vehicles from 1960 - 1982.
Go to Vintage Repair Manuals and Select the category you need. This covers the vehicle you need repair information for. This was the only place I found that covers your 1960 - 1982 Vehicles. And best of all, its FREE!
UPDATE: They no longer are available there now. I am currently looking, if you find a place let me know.
VINTAGE – The new Vintage Repair Center contains “vehicle specific” repair information from the mid – 1960s to 1982. Almost all US Domestic and Import cars, light trucks, and vans are included. Categories of detailed text, tables, and diagrams include: Engine Mechanical, Chassis, Electrical, Wiring Diagrams and Engine Performance.
More Coverage Than Anybody