[drh4683]

I always enjoyed working on the ctc31. I did a total restoration on one I picked up at the curb 2 years ago. Needed the ususal 6GH8 change. When you tested your 6GH8s did you perform a life test on them with your meter? The life test is critical in determining if the tube is going to work satisfactory or not. Also, did you check the tubes for grid leakage? gh8's are known for bad grid leakage, or also called grid emission.
The one set did have weak color and that is simple checking/replacing of the mixer/osc and check your pix IF tubes, those can kill your color, or weaken it. I dont want to rule out tubes just yet, as they normally cure the ctc31 color problems. Should tubes definitly be ok, I have some helpful pointers on aligning those chassis. Since you get color on cable, it sounds like a front end problem.
Keep us posted! By the way, can you show a pic of that set? Remote sets need to be shown! hardly any of those out there!