Question for those more knowledgeable. Am putting this thing back together after doing valves and belts and noticed that the horizontal intake manifold is extremely rough and crusty. The vertical I replaced when I first started working on the bike because the mating surface wasnt completely true and I thought it might be causing a vacuum leak. And I dont remember it being this rough. I am leaning toward replacing it, but wanted to get some input from some of you more experienced with this motor.