Hey Mick, nice ribs!
I've got that same thermometer and love it! I don't use it for ribs though. My personal thought on ribs is, let them pull back from the bone a bit, you can tell/see it when it happens. Once there is somewhere around 1/2 inch of bone showing then you should be pretty good to go. All ribs are different, so don't plan on a set "eating time".
Personally, I'm not fond of really moist ribs. Nothing real dry, I just kind of like a rib that barely takes a bit of bite to pull off the bone. I don't ever wrap mine, just keep 'em low and slow, wait for 'em to pull back from the bone some and you should be good to go. Those do look line fine ribs though, good job!
P.S. - Did you find some lump charcoal?