1999 Amigo, Audiovox CCS100

I am installing the Audiovox CCS100 on a 1999 Isuzu Amigo. I have everything installed per the outdated instructions but it doesn't work. I have tested the wires per the instructions and everything checks out. I do not have the blue tach wire hooked as I have found and connected the VSS wire at the speedo. Some on here say not to connect if the VSS is found, others say it should be as a safety percaution. The instructions say to connect the tach wire at the negitive side of the coil. The tach wire is supposed to be a BLACK/ red wire on my vehicle. Isn't that the positive side, though? Can I connect at one of the coils over the cyclinders. If so, which one and which wire?

Thanks. 

Ok, I found the problem. The VSS wire in the kit is so small that it does not get pierced when using the connectors supplied with the kit. I reconnected the wire at the PCM (I had it at the speedo before). While I had everything taken apart, I connected the blue wire to the tach PCM, also. I didn't use the kit's connectors there either. Because of the lack of room, I stripped the cover off both wires, twisted the kit wires tight around each, soldered and taped them up. Everything works fine now.

I wish Audiovox would update thier instructions to include vehicles made in the last ten years. As it is, I would recommend the kit to any one needing a low cost cruise control. I would tell them to have a wiring diagram handly for their vehicle, though. It will save a lot of frustation.