Car won't run past 60mph

A lot of that Lokar adjustment instruction has to do with making sure that you don't adjust it too short; if that happens, then when you push to WOT, the cable will be jamming the kickdown lever hard against the kickdown valve or some stop inside the trans, and something will have to give: the lever, the shaft, the cable, the valve..... So that instruction really does not set the length for the shift point but for avoiding damage.

The stock linkage has a lot of design features, like the slots and springs, to avoid that. There have been some setup mods developed by clever people to prevent that with the Lokar cable while getting the shift points right. I don't have a pix right now.....