difinatly go twards the cab on your exhaust manifold ive had it done in two of the same trucks bolth had same mods done and one was on inside one was on outside and the truck with it on the outside always "ran cooler" then we moved it and they ran almost exactly the same

 

When i bought my truck the past owner drilled in the exhaust behind the turbo and i would prefer to have it before the turbo. Do you guys think it would be worth it to re drill and plug the hole in the exhaust?