when getting new cams put in along with valve springs and ti-retainers, does the head have to be removed first? or can they do it without removing the head. And would u recommend if that they do take it off to change the head gasket? personally i feel it doesnt have to be changed...the engine only has 44000 miles on it. How much $$ does a job like this usually run for and how long does it take. I have crower stage II cams with valve springs and retainers soon ready to go in...what else should i get before i go through with this. whats your oppinion?