can someone suggest a good maintenance manual for a '67?

 

Go to Camaro Research Group and download the Service & Chassis manuals along with the AIM (Assembly Instruction Manual).
An Owner's Manual would give you the maintenance schedule. The Service & Chassis tell you how to do the maintenance and repair.

 

Check out Classic Industries, you can order the Chassis Service Manual, Factory Assembly Instruction Manual, and the Body by Fisher Service Manual.