Finally checked out Crown Auto Gallery (Lexington, KY) after seeing their lot on my commute for months. They keep around 39 vehicles, mostly diesel pickups. They were totally fine with my mechanic doing a once-over, which honestly settles half the trust question.
Lot address: 2971 Haul Rd, Lexington, KY. Visitor parking: Front-lot customer stalls facing the office; overflow on the side street near Lexington lot gate.
Paper side: licensed with the state (looked it up), about 72% of stock has title in hand per the office, and they offer a 6-month powertrain warranty on newer units.
Overall: good people to deal with. 10 years in business around diesel pickups, doc fee $449 and it's on the window sheet, no games. I'd send a family member there.