This has been bugging me for a while. I need some input. I have a slight crack in my exhaust manifold on my 01 XJ. Decided to show itself after swapping the engine. I switched out the 0331 head with the 0630 before dropping the new motor in. With the 0630 head on, would i technically be able to eliminate the twin collector nonsense, and put a 98 XJ exhaust manifold on if I drill out the bung holes for the o2 sensors and not trip a CEL?