Need a schematic for CAT SL1 Mark 3, or just a picture of the insides of unit

Here's my problem. I attempted to have this unit serviced by a local repairman. It was a small issue (the mute switch snapped off) and CAT wants a flat fee of $1500 plus ship to take care of the repair. That seemed like a nonstarter. The local repairman messed it up and now I need to take it to another repairman. The problem is that the first repairman failed to take a picture of the interior of my CAT before he started work, and the second repairman really wants a picture of what the original wiring looked like. I have no such photo. Does anyone out there who has the same preamp have a picture of its guts that you can send to me? It would be a great help. Thanks in advance for any help.