Thank you for this very timely post with lots of good tips. Coincidentally, I did almost this exact cook yesterday.
3 racks of baby backs, trimmed, halved, rubbed with Swamp Boys Rub (thank you again, @Rub), and hooked.
Approx 2/3 charcoal ring of Cowboy lump, maple wood, and a small chimney full of lit lump.
Left to hang for two hours before saucing with Swamp Boys sauce, and foiling with a small amount of apple juice and back on for another hour.
Just before serving I unwrapped and put them back on for another 15 minutes.
This was my most successful attempt at ribs to date. I really enjoyed the taste and texture imparted by hanging direct over coals. Thanks for looking.