HelloCustomerand welcoem to justanswer.com,
There are several places you can find the hook ups you need.
This is an automatic correct? t i have enclosed a picture of the A/T reverse relay it is located behind the glove box on the passenger side. click here
You will need to splice into the green/black wire on terminal #1 of the relay.. that is the siganl to the reverse lights. When the reverse lights are commanded to come on this wire has power.
In terms of power and ground the passenger fuse box is to the right of these relays. you will need a test light. Find a wire that has power only with the key in run. and I am sure there is a bolt or somewhere near ther where you can attach a ground.
let me know if you need any other assistance