sound like to many helpers. you could of drive it in cocky? i only had a ford 300 6 like that. i had to send it out for in line bore and get the cam housing bore open up. ford used one under size cam bearing in the block. came form ford that way .sounds like you mix them up positons? like ch-1 is #1... ch-2 is#2or5... ch-3is#3or4... the oR means they will need them to go in the posted positions