I understand the above post. The guy is trying to make a living. He's invested in the whole enterprise and needs to make a certain amount in order to keep it going. It does require patience explaining the basics over and over to new and rookie customers who want to save a buck and end up spending five in the process. Things go wrong even when you do them right. That's why they want to use their own parts so they can be sure about the finished product and make a dollar on the parts, something they need to do in order to stay in business. Keep in mind that they aren't purchasing corporate jets with that money. They are paying the rent and the light bill. And when they go out of business because they couldn't do that, you will miss them more than you think. Building motors is fun but there are hassles. I've gotten to where I really like the whole simplicity of crate motors. There's an economy of scale there for the manufacturer. It then frees your time and frees your mind for other things.
Don, I've R&R'd a Pontiac engine three times dealing with a rear main leak. It now leaks in the front. Don't give up the ship!!!!