idk if alot of people know this or not, But i see alot of varying prices on the 4 bolt manifold. but they can be had cheap. 85$ new to be exact
2008 CHEVROLET SILVERADO 1500 Intake Manifold. they share the same part number as the tbss manifolds.

Iv bought and installed on on my 2500hd before it fit perfectly and worked great.

dont wanna step on anyones toes but this may help a few others in need.

 

tbss and nnbs have a different part # at rock auto. i got the tbss on my 2012. ac/delco for about $160 shipped to my door.

 

you sure? i went under an 06 tbss and got the same part number.