The retarded side of CARB is their unwillingness to move away from oem equipment, and move to tail pipe emissions only. As long as the non oem part doesn't increase emissions, it should be legal. They just need to use more logic based reasoning which would have avoided the whole MTB fiasco, which cost us millions of $$ in extra gas cost and now clean up costs, and MTB additive replacement cost.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed