Is it really recommend to block off the back two areas for the coolant lines. I'm installing the LS6 Intake Manifold and that's what the directions say and I know you should pretty much always follow the directions but curious on the reseaoning is for this. Is it that the manifold will crush the lines if they were there? Thanks yall!!!

 

It wont fit unless you use the LS6 coolant lines.

 

Yep it is not going to fit unless you change them.

 

The LS6 intake is flat underneath, so the stock pipe(s) will keep it from sitting/sealing correctly. Helped a friend do his and we used the plugs/new front pipe.

 

Also dont forget the seals for the front cross over pipe and seals for the rear plugs there little metal clips that have a seal to help get better seal so coolant doesnt leak out.