You will find that all the different operations are done different ways by builders. Some like to leave on the sq ends to do holes and lips others like to do belly holes first and use them to do all the other machining. I prefer this method. I built a fixture that is fully adjustable to any size, length, dia. plug I make. It is way overdone but I know no other way
, I am retarded, but you could build something similar out of a hard wood. I use a fence on the bandsaw if I am doing more than a few and slide the jig against it. Good luck and get used to getting pissed it is part of the process.