I'll have my Crower 403s put in this weekend, hopefully(if the Crower valvetrain kit comes in)...they are used with about 1-3k miles on them, good condition and the surfaces are in good visible condition...is there anything I should do to prep the cams out of the regular procces before putting them in my head since they are used?? is any type of surfacing or anything needed or just hand them over to the shop and let them install them? the engine shop doing the install will know, but I just wanna know myself also before I hand them over. thanks