i was looking up 383 strokers on how to build one and it says that if you have a stock 400 crank you need the main journals ground, what are the journals and how much do you need them ground, then it say you use 350 rods but they need to be reconditioned, what does that entail, it also says you can use a 3.75 crank but what is the difference between that and a 400 crank, it also says to have a 383 you need it bored out .030 over but what do you have when it is bored .060 over, like a 390 or something and then does that affect the performance or anything even significant