as i have little experience on ohc engines, i have a few questions.

-do the heads need to be removed from the motor to replace the cams, and if so, can they be removed while the motor is in the truck?
-how much labor is involved in chaging the cams if i were to pay somebody to do it?
-is it worth going to stage 2 cams on stock heads, or would the gains be marginal with respect to cost?