If you are using the same aftermarket reg/rec as linked to in that thread, a correct unit for the '79 and older alternator, then you don't want or need to install the nylon screws. On the older alternator, the inner brush is grounded full time (through it's mounting screws) and the outer brush is fed regulated power from the regulator. So, positive in through the outer brush and negative out at the inner brush. This completes the circuit. By installing the nylon screws on the inner brush, you have isolated it from ground and the circuit is no longer complete. You will get no charging output.
You must connect the black wire from the new reg/rec unit. It is the ground wire for both the reg and the rec.