i would like to add a 3" lift. How do i get the mounts off. There are no nuts on the inside of the truck under the carpet? And can i take the whole body right off

If you're working on a Tracker/Sidekick:

They are studs welded the the body(except the two in the front) not bolts
You need to remove the nuts from underneath and lift the body.

See here for a great homemade body lift article:
http://www.zuwharrie.com/content/view/11/27/

Calmini 3" body lift install(similar to homemade really)
http://www.zukiworld.com/month_100101/feature_spyderman.htm