Change a 904 to manual valve body

Have a rather butchered 71 Dart. Long story. Original motor was a slanty, swapped for a 360 before I purchased. Kick down linkage was MIA on purchase and I wasn't aware of it (I know, I should have checked), so some miles were put on it, probably less than 100 but enough that I knew it wasn't right. Hoping the trans is not trash at this point. Tried using a Lokar cable, but could not get the adjustment anywhere close, always too much slack on both ends. Without going to steel linkage that I would have to find for this car, would a manual valve body be an option for a daily or should I just try and find a full linkage set and fight it to get it set up right?
I've had 4 speeds and 727 with auto VB and manual VB. I would not consider an auto VB in a performance car... you have very little control. 4 speeds are fun but a lot of work. Stop and go traffic w a HP clutch is not fun. I love my manual VB... Shifts when I want, hard & fast, can leave it in 3rd for easy take offs. Pair it w a great shifter like Turbo Action and it will shift easy and positive.