HELP! Charging/Wiring Problem

My '73 Swinger has a charging and/or wiring problem and I can't figure it out. :angry7::angry5::angryfir::angry1:angry9: Originally a 318 car, I got the car with no engine and have since installed a 340. It has a Mopar Performance chrome electronic ignition with a Mopar electronic voltage regulator and a stock ballast resistor. The original wiring harness is in the car and it's in reasonably good shape. I have repaired a couple of the wires going into the bulkhead connector and the rest looks good. I have already bypassed the ammeter in the instrument panel and I want to run an 8 guage wire from the alternator to the starter relay, but the alternator is not charging. The alternator currently has the stock (for a '73 318 ) 12 guage wire running from it to the bulkhead and I know it's not sufficient for my set up. The alternator is a new one from Bouchillon Performance Engineering that is 75/50 amps (BPE5302) with 2 field connectors. A second problem is that I only have one field wire-the 18 guage dark green one. The 18 guage dark blue one is missing. I looked at the wiring diagram and ran an 18 guage dark blue wire from the 18 guage dark blue wire on the voltage regulator to the other field terminal on the alternator, but it's still not charging :cussing:. With the ignition off, I'm reading 12.57 volts at the alternator and 12.6 volts at the battery. With the engine running it falls about 2 volts at both. Also, I am not sure if my ballast resistor is wired correctly:dontknow:. It has 3 wires connected to it. A 16 guage dark blue and an 18 guage light blue/yellow on one terminal and a 16 guage brown on the other post. My voltage regulator has an 18 guage dark blue wire and an 18 guage dark green wire in the stock connector. Please offer any suggestions before I ](*,).