I have a 92 Cherokee 6cly 4.0 auto,4x4. alternator went out, I haqve the alternator from an 89, that uses a plug to connect to the harness. the 92 has three separate wires, I know where the one goes but need to splice the plug to the other wires, what I do not know is which goes where. also there seems to be some kind of ground piece that attaches to two lugs on the 92's case this has a 'box' in the middle and a wire going back into the harness. the 89 does not have the logs, can i simply ground this to another bolt??

there might be some way to make it work, but effortlessly, no..... the 92's alternator output voltage is externally regulated by the ECM.... the 89's internally regulated.... external regulators can be installed on internally regulated alternators, but could be quite involved the other way

the "box"/block with multiple wires molded into it are ground connections & field coil wires.... the ~2" thicker (10 gauge) black wire coming out of it & attaching to the case is the ground, & the "o" ring connector protruding out of the block (without wire) & also attaching to the case is just for mounting, there's no wire connected to it inside the block.... the 2 thin (14 gauge) green wires are the field coil wires.... one reads/senses the coils the other controls the coils electricity

Not terribly difficult, Battery wire still goes to the battery.
Ground through the case
On terminal L, you need a switched 12 volts, that has a 30 to 500 ohm resistor in the line. Normally this is routed through a bulb (idiot light).
Ignore the rest of the terminals for this use.

Ron