abe

..maybe all of you know this, but pelicanparts.com has a section that you can see parts and diagrams. Also for fun take a look at the design of the exaust manifold of the S vs nonS. The non S has a better design(three pipes attaches to the one exaust pipe independently..the S all meet at one point) and that might be one of the reasons that changing it on the S makes a bigger difference than the non S models...in my humble ignorant opinion.
abe

dstrimbu

Yah, the more I look at the "S" manifolds, the more I think of the Porsche farm implement days... :-)
But the design is probably good for low-end torque production...
The X51 seems to be the intelligent "bang-for-the-buck" swap.