Went to get him this past week. Was surprised by what seemed to be a litter of shy pups who, when smelled you, would back away.  Volhardt test wouldn't work. Pups wouldn't engage.  Made a semi decision on two based on the breeders notes and what little interaction I was able to get holding them on his back. Decided to return the next day, and asked the breeder to engage with the pups where they wouldn't notice me. Difference was amazing. Sat, watched, evaluated and started engaging with them. She left, and when she returned, all the pups went close to where she was, but one of two I had picked out the day before. We brought him home. I now have a little shadow. He is 7 weeks old. Has learned his name in 2 days. So far anyone but my wife and I speak, or try to engage him, he just sits and looks at them. No tail wagging, nothing. Just watches them. He hears a new voice, he stops what he is doing sits, and just watches them. Have already seen his propensity for fearlessness with the sheep, standing his ground when they are rushing out the gate, and trying to engage with Lexi in a fight for her barking toward us. Had to hold them apart and calm him down.  

In training him I intentionally avoided protection training or I anything I saw as fostering aggression. In hindsight I wish I had gotten helpers to rough house with me in front of him as a puppy, and did bite work to ease his protectiveness, teaching him to control it and allay suspicion.
He really surprised us with getting territorial as early as 4 months.
Even though I have taken him everywhere I can I usually work alone. So on a job-site he doesn't like people around the truck, or anyone touching my tools.
Have had a couple close calls recently from people pushing boundaries. Even though told otherwise, they assume since he has never shown aggression in businesses when they get close they have liberty to get as close to him, me, or approach the truck elsewhere.
As long as he is in a heel, or down, close to me he is okay, unless approaching me while I'm in a vulnerable position. At the 4th fireworks display I had Ace in a down beside me as I sat in a lounger and he was doing very well with the commotion of the fireworks and commotion of people. A man returned a knife he had borrowed, and when he handed it to me, I assume the combination of something in his hand, speed he handed it to me, and leaning toward me made Ace see it as a threat and he came alive. If I had been standing I don't think he would have reacted at all.

Regarding trucks, my wife can get in truck anytime, as for anyone else I use rule of possession, meaning they get in first while he is in a heel beside me, and then we get in.

An interesting note; anything they bring in with them, they can set on dash, cup holders, etc., and remove. Anything else is hands off.

It's fascinating he is actually aware enough of everything in the cab of my truck to know the difference.

Updated goals are to find helpers to work around him to make him less reactive, and wait until given a command, or physical aggression is shown by the other party.