S.C., follow rainboe's advice as it's good gen. Been a long time since I flew a 737-300 so no NG experience, but I tend to fly all eng inop approaches with the rudder trim neutral - that way I know where the sucker is. If you keep the slip balanced the FD will give you great info.
Reference thrust settings, as a [rough] general rule thrust = fuel flow, so use the same total fuel flow to get a ballpark thrust setting. Not sure if that is easy to see on the NG
Best of luck!