Put an LS2 in my 99 WS6. Fired it up for the first time yesterday, and within a minute all the instrument gauges and display on the radio start acting up. First thought was ground wires, so we went back over them and even did some over again. There are two that come off the neg on the battery one is close and goes to the frame and the other one follows the starter wire and we put that one on the side of the block. There is also a little one we put on the starter itself. On the drivers side there were two that we know of we secured both of them to the frame near all the brake lines in two different spots. One of them I was sure of, the other I thought might go to the block and not the frame. (Does that matter?) And yes I got the ones on the back of the head. After doing a lot of reading on here I have tried giving the battery a charge, (which is like new but did sit for about 6 months) and did some voltage tests on the battery and at the back of the altenator. After giving the battery a good charge I tried starthing it again and for a little bit everything seemed fine, then I flipped the parking lights on and BAM all the gauges go wacky! Shut the lights out and they go back to norm for a while. Another thing I did was put the four ways on and the oil pressure gauge jumps up and down slightly in perfect rythim with the blinkers! I was getting about 14 volts at the battery and altenator with key off after the charge. When I start the engine it drops a little to like 12.x and then when I flip the parking lights on it drops into the 11 range. Does this mean the altenator is shot?? What is the best thing to do if I think its the altenator?... We have an advanced auto near by that supposedly does a free batt/starter/altenator check?? Should I just get a rebuilt one and try that? or should I take the altenator out of the car and take just that to my local starter/altenator shop and ask them to test it?? Someone posted on here that sometimes you get a false positive on the altenator test because its not under load or something like that. Just looking for some advice on what to do next. Thanks

 

Anyone??