Well first off, Have fun well you are out here!! Let me know if you have any questions as the time nears! but items to have
1. Charles Wells books
2. Food, water
3. Tow Rope
4. Basic Tools
5.Recovery Points
Out of curiosity where in CO are you going? I will help as much as possible! There are many trails here in CO you can do totally stock, so you will be fine!
Online research for trails:
TrailDamage.com
4x4Trails.net
If you are planning on going to harder trails I would highly recomend skid plates and sliders!