Still no alternator function- Getting depressed

[Indiana_Red@hotmail.com (Ken B)]

So this is the second reman BOSCH alt from BowWow that i have tried.  I get
about 12V from the batt posts with the engine running or not.  I get about a
.5 v drop when I hit the flash-to-pass headlights. (bently says this drop
means prob not a bad v-reg)
 I have additional ground wires:  4ga from alt adj arm where it bolts to the
alt all the way to the (-) post, 4ga from back of intake to the coil bracket
(replacing the stock flat strap)  Stock but reconditioned mount surfaces
from neg post to body under battery-continuing on to a tranny bolt near the
green end cap.
I have a couple feet of leftover 4ga black wire for another "leg" if i get
strong recomendations
I have also tried an additional new voltage regulator that I have.
Bently says you are not supposed to run that alternator when it is not
attached to the battery so I cant realy test it only.
The stock harness that has the 4-6 ga red wire and the 1mm blue both have
continuity but this is the only thing I can think of that has not been
replaced/upgraded.
There is a major but simple problem here somewhere.
The battery is old but it charges up good with my sears trickle charger and
is then good for dozens of starts while trouble shooting for a week or two.
So it holds V ok.  I think I ahve allready swapped in the batt from my other
car with no change but will 2X-check.
Lastly I am about to crawl under and take off the stock ground strap and
sand/clean reinstall etc, but with my other ground upgrades this is not
likely fix.
Anything?  Anyone?
Thanks as allways
Ken
1979 Scirocco 16V -  Almost done
81 Deisel P/U - Rescued from neglegent PO
VORTEX:  "Indiana Red"