There is really only one fix for the TKO boxes, it is the Liberty fix. Doesn't matter who installs it, you or someone else. If you want the transmission to shift properly you need the Liberty fix.
Dwight has been to the same rodeo and the ending is predictably the same — Liberty. Like Dwight said, he had tried 'magic fluids, shifters' et al. The only thing that fixed the problem was the Liberty kit. You will not be disappointed, however, you likely will be disappointed if you choose a snake
oil fix.
Ed