Best Gas tank for under the bed?

[abadsvt]

I am in need of a gas tank for underneath the bed of my truck. I plan on bagging the truck and don't want to see the gas tank from the back. I know they sell some alluminum ones, some stainless ones, and some steel ones. I was looking at the one that is in the Copperhead truck but dont really want to spend $800 for a gas tank. My truck is going to be a show/driver truck. One more thing. It needs to be for fuel injection. Thanks Josh