Loved your very tall frame discussion and finds. 68cm is too tall but I do ride a 67cm and like you I own several very large bicycles from the past. The older very large frames fit me better than the modern ones. I don't want to pay for custom frames as long as there are appropriate used factory made frames for much cheaper and yet the quality is there. I've also seen frames advertised as XXL but you end up with a seatpost sticking way out of the frame. I've seen these frames with the seatpost out so far break at the seatpost tube. Trying not to anger the gods of geometry and frame overloading. I agree with your discussion about thieving. My bicycles are basically custom to a large degree and have a lot of nice expensive parts on them. My go to the store bicycle on the other hand is a Worksman cycletruck that is a grungy, rusty, one piece crank klunker and I lock it with a Kryptonite and heavy hardware store chain with lock. The locks are mere annoyances in this day and age of battery powered grinders. The idea is to present a bicycle nobody really wants. I also don't park at a regular time or date so planning by thieves is thrown off. So far, 25yrs with it, so good. Good luck with your find.