Alternator Or Wiring?

[92-SSRG]

First while I was driving my 92 Surf SSR-G with the 3-VZE V6 the lights started dimming and the Battery voltage meter would go down and up with every instrument I used, then the car started to die while at stop lights. It finally died at my destination and I thought it was the Battery not holding the charge so I bought a new one. Everything worked fine for a couple hours until it started again. Ok I thought that it was the Alternator. Took the alternator off and took it to a guy to test it. He says its fine and that its the wiring. I put the alternator back on and reconnect everything and jump the car. While its still connected to another car via jumper cables the car performs as normal. All instruments work, the radio doesn't cut out, everything is fine. Disconnect the jumper cables and it goes back to the problem of dimming and the voltage meter drops. I think that it is still the alternator but here in Okinawa those are hella expensive and I don't want to be wrong.

Also, the car makes a wirring noise whenever revved and when I turn the wheel. Sounds like the powersteering. Think the two issues are connected?

I need answers here as Im tight on cash and need my truck to start working. Any help is appreciated!!!!

-Ben