The phrase "Push-on" or "Screw-on" was used in reference to the cap type. Early M117 engine cars had holes in the top (push-on) later ones had studs sticking out of the cap (screw-on). For the most part, aftermarket wire sets are poor quality. They sell some decent ones right here at Parts Shop. As far as the ends go, yes... the metal shielded ones are the way to go.
Be wary of aftermarket sets that use "suppression" core wire. Our cars use metal core wire (and non-resistor plugs). A bit unusual for most of the "Parts-R-Us" guys.
Regards,
Randy D.