you can look for hone/ machine marks in the main bore and they are like a thumb print and if you can not see this the caps allmost all the time are never right on center of bore to center of the main caps so if you put the cap on the wrong place then you can feel the bore with your finger the cap will hang in or out where the cap bolts to the block . and when you think you have them right. check with a bore gauge if the caps are not for this engine then it is time for cap fitting and aline bore i have done this many times for new caps on a old block