Implement System Calibration will require Cat ET. Thinking about it, it might be a good idea to get ET hooked up to it and produce a Product Status Report (PSR). This is an Adobe pdf file that could run to 20 pages listing all the settings/adjustments/calibrations, etc, et of everything on the machine. Often when reading it something just jumps out at you "this isn't right". What I'm wondering (amongst other things) is whether or not your machine has the correct electronic configuration in it for the 6-way blade that I assume it has from the way you speak about the hydraulics. The Implement system has to be set up differently between a 6-way blade and a standard single-tilt offering, and it requires ET to change between modes. It's unfortunate that you have no idea of the history of the machine, but I had to ask. I'll send you an electrical schematic.