I get what you're saying about modulation vs key change; it makes sense. Like many lazy(?) players, I've always ignored the modulation in Bobby McGee due to "technical difficulties". It's a bit harder to ignore it in this song. I haven't paid enough attention to the basic music theory in a long time, so I pulled out my Circle of Fifths and other notes and I'm getting back into it.

I think I'm mostly there, but still some work to do. Enjoyable work, though. Thanks to everyone who chimed in, and feel free to keep chiming if the mood hits you.

JimB