I can't post a pic here for some reason, but I've done dozens of these adjustments over the years. Typically with the TV lever pulled forward you can get full rearward travel at wot. This one lacked that full rearward travel by and I'm guessing, maybe 1/4 " max. I biased it by pulling the lever just off the fwd stop by about that amount. So I have full rearward travel at wot. The throttle linkage pin is touching the rear of the slot in the TV linkage and of course it moves immediately with throttle opening. This is the best I can do. The linkage is the full rod type as opposed to the bellcrank type. I was surprised when I rigged the tv open to test and the idle was affected as well. My understanding is the slot in the linkage was supposed to absorb that but I never tested that. My guess is that there are some mis matched componets contributing to this. All this aside the trans works well except this issue. It is more than slop in the driveline. If it was, it would be like half a turn of the pinion.

edit: As a further test, I pulled the shaft. Again, rear seems not to be an issue. Shaft could turn easily in one direction and more difficult, but not impossible in the other. I compared that to two 727's I have out and seemed to match one. The other which has a known issue could turn easily in one direction, but was about impossible to turn the other. I'm discounting that one, but these are things I never really looked at before so I don't really know. Was able to attach pic also.