1993 Nissan Sentra starter

Hi, when I try to start the car, a terrible noise, similar to a fork being in a garbage disposal, eminates from the area of where the starter and engine intersect. Previous to this, the starter was making a squeal, which, as I understand it, was caused by the failure of it's pinion gear to retract properly. My question is. Is it likely that the starter, or the flywheel, or both, have failed? I can handle replacing the starter, but I doubt I can do the flywheel.