1994 Gmc Sierra question

I am about to buy my thermostat and i dont have many big mods.

5.7L 350
Air Aide Cold Air Intake
Helix Power Tower TBI SPACER
Tru Dual Exhaust

Plans- Headers
Different Exhaust setup
Possibly a chip

So really with all that being said what would be a good thermostat to pickup?

( BRAND, DEG )

And really how hard is it to put in?