Re: cobra shift cable
How did you adjust the bellcrank. I suggest getting the tool to hold it in the correct position. It is possible to do it without it but if you don't get it perfectly at 90 degrees, you will have more throw in one direction than the other and that may be your problem.
Also, how much "lost motion" is in your control? What I mean by that is that when you move your control lever are you getting the full throw that the lever is trying to give. If the control is worn, the connections at the control are loose or the cables move around, you will have lost motion that limits the travel back at the drive. Use tie wraps and tie up the cable that goes to the control back to the engine. that will do a lot to minimize "lost motion".
You should also read this entire site:
http://www.hastings.org/~stuart/cobra/