I was a little scared of tapping the wire also. But I'm sure happy I did. I know it doesn't make you feel better about it, but if the VP is going to go. Some have tapped the wire and had no problems at all. Others have lost the pump immediately. Do some searches on the subject and you'll find info on both.
I didn't ask, do you have gauges? You are definately going to need an EGT gauge with a comp. It is really a good idea to install gauges before any modifications. It will give you a good baseline of where you are at now. With a '99 you should think about an EGT and Fuel pressure gauge as a minimum.
Justin