www.hydroe.com sells manuals that may help. I was brought up on the scissor top. In and of the shop when I was a kid. Any questions I'd be happy to assist.
How true Peter lol. Worn out bushings and linkage ends with no parts available, I would give the customer money to go away. That top was mediocre when new ,let alone now.
We made a Eldorado with a scissor top a few years ago...but I dont know if it wars a '74. But i think i have still some documents about parts and maybe a installation guide. I must have a look. But i cant promise!
Before I even start this job I would make sure the doors open and close properly. These cars are sooo big that they tend to fold in on themselves. Rusted frames tweek everything. If you can't find a manual contact me and I can send you one. 320-524-2030