Can you run 540 RPM implements with a simple adapter on a 1000 RPM shaft or do you need to change the entire pto?

if you put a 540 adaptor onto a 1000 spd PTO of a tractor you must keep the engine rpm low enough so that it only turns at 540 PTO rpm some tractors have a selector lever for 540/1000 on some you must change the PTO shaft and it engages a different gear inside the tractor