so I guess either check works. multimeter or test light.

multimeter doesn't need the battery connected. So it might be safer.

they way I described gives you an instant read instead of having to look at the meter. so I prefer it as faster to check circuits.

you should get a light at the alt case, but not the big stud on the back.

unless it is grounded. then I would pull the alt and have it tested as well.

if you follow the circuit path, you have power at the test light to power. It would be like touching it back to the pos terminal on the battery. nothing should happen.
IF it lights, then you have a path back to ground.

In some cases, that might be correct, like I don't know about the 2 field vr or the electronic ignition.

in others this should not happen.

The relay stud that normally connects to the battery should not light up. again like touching the end of the test light back to the pos of the battery. it shouldn't complete the circuit.

if you pull all the wiring from the relay I would check each one to find which one causes it to light up.

my way you don't really need to plug it all back into the bulkhead. Just make sure the ends are connected to whatever they go to. touch each wire in the connector and see if it lights.
if it does trace it or disconnect the end and see if it still lights.
if it does the wire has a break in it and it is going to ground.
if it stops lighting, then check whatever was at the other end to see if it is supposed to be grounded.