I use those connectors for many years using the Scotch lock crimpers, I've seen more than one Tel.Co employee crimp them with thieir nine inch pliers, NOT GOOD tskdown
The pliers do not force the blades in the connectors to seat evenly on the wires which can end up creating a high resistance connection which will end up causing problems with noise and no connections sometimes whiney

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)