Thanks to both Toms (and everyone else) for all the clarifications. Words
are cheap, but I really do appreciate the help. I'm ready to let the
Electrician lead the way, but now I can make sure all is on the up and up.

Of course, knowing me, there's one last detail. Power comes into my house
to a main breaker box, then goes out to a separate modern service panel.
The main breaker box is nothing more than a 100 amp breaker with no bus bars
or anything like that. (Sorry if that was obvious). Power goes through
this main breaker and over to a separate modern service panel. Likewise, a
4 gague copper ground conductor leaves this main breaker box and goes out to
the modern service panel.

Currently, the GEC leaves from the main breaker box and goes out through the
basement wall to earth ground.

If I understand correctly, from what I've learned here, the new setup should
have the GEC going from the ground bar of the modern service panel out
through the wall to the grounding rod, instead of the GEC coming from the
initial main breaker box. Is that correct?


(If the correct method is to run the GEC from the initial breaker box, then
does that mean the water pipe ground conductor should also be grounded to
this same box as opposed to using the modern service panel's ground bus
bar?)

And with that, I'll let this long thread putter out. Thanks for sticking
with me and my poor newserver access. lol.