I need to know what other interfaces i need for it to work with the new headunit

Nothing!!! You cant use the OEM tuner with an aftermarket deck..

really so just plug and play no other wires or anything like that but if i want to keep the steering wheel controls working i do have to buy a interface.

but if i want to keep the steering wheel controls working i do have to buy a interface.

Yes.

really so just plug and play no other wires or anything like that

well you will need a dash kit(to mount the unit), a wire harness (so that the unit will plug into the truck), and a antenna adapter (since GM's use a different type of connector)

and hes is correct, there is no way to make a factory XM tuner work with any other radio other than the factory, if you want to keep XM, then you will need to buy the pioneer XM module, same goes for the steering wheel controls

and the parts you will need will depend on what year your truck is.