Introduction, and trans issue

How did it shift before you modified anything? Those Lokar cables can be a source of contention sometimes with Mopars. Usually the best is to make the stock linkage work if at all possible. But tell us how it shifted before you modded it and we can go from there.
Agreed. Sounds like he may need to do the old wide open throttle thing and adjust from there. The shift points don't sound bad but not enough travel for passing gear. Depending what year transmission and modifications, it might not have "part throttle kickdown" but only 3-2 passing gear downshift.