you would use the KB 361 that will get 434 with a454 crank you may cut the deck of the pistons you have done it with a piston vise i done the job many times . domes need to get trimed to and re fly cut cheaper buying the pistons to fit .has for cams i could help you but sounds like you have a cam company your dealing with so call them i machine and build alot of BBC i use hyd roller s for street and sold rollers for hot street and off road . i have some roller cams and GM cast 454 cranks if needed last 402 i built and machined is 460hp and 500 tq with some work i do to the heads