well getting all my parts together for the new engine for the mirada. just got my b1 heads and world block. waiting on rotating assembly from muscle motors.(pistons are getting made.also have a few questions on b1 heads. how thick are the spacers for the intake?someone have a set laying around that they could measure? and where do you put the oil drain holes that i have seen and have heard are needed?any other info would greatly be appreciated on setting them up to run.right know they are new in the boxes that some never used so i have to send somewhere to get set up. thanks much