92 Integra GS-R

Ok, so not but a few months ago did I rebuild the alternator and everything was going fine. Now the lights just fluctuate bewteen dim and regular brightness. The battery light comes on (flickering) every once in a while. The car hesitates in high gear at low speeds, and now the oil pressure light comes on at start-up.

I have a multi-meter I have to dig out of my stuff, but I was thinking to use it at the battery to see if I am getting a constant flow of power.. if not then the alternator must be acting up. The shop gauruntees the rebuild against everything except water and oil..

Any ideas or suggestions?

Thanks,
Trevor