No difference between intake & exhaust. The bridges are the same for the 6 and 8, not sure about the rockers. The OEM rocker bridges were 1 solid piece of cast aluminum. The aftermarket replacement bridges have the aluminum pivots with a stamped metal bridge (probably cheaper/easier to make).
MC sells the bridges and rockers here, go up to the top and click on the E-store, or try this link:
http://www.bulltear.com/catalog/index.php?cPath=21_35
Bob
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