I don't think a 727 can land itself so at some point regardless, you will have to disconnect and land it yourself. The autopilot will take some of the load of getting on the localizer and glide slope but you will need to understand what your are looking at to take over at some point.

You would be better served by learning the ILS approach technique on a slow plane like the 172. You will have much more time to make corrections to your attitude. If you are not already proficient in a more forgiving plane, you will just get frustrated in a fast mover. The gauges for the ILS landing are the same regardless of the aircraft.

Dave