((((((((hugs))))))))
My DD is a lot like your #2 and always has been. She's still taking a looonnnggg and painful time to finish up her 2 yr molars, and though we no longer (knock wood) have those nights of banshee screaming since she can verbalize better, we still have A LOT of sleepless nights. You're not alone - C used to do the exact same thing, waking up and going 0 to 60 with the intense, shrill cry.
All I can really say is keep on keepin' on, sounds like you're doing a great job trying to help him. I third the vote for tylenol/motrin if it helps you both get some sleep and him some relief. Have you tried any homeopathic remedies? We've had some luck with them, particularly the teething tablets and sometimes the plain Chamomilla.
Also I'd put in a word for the book "Raising Your Spirited Child" because I really wish I'd found it when C was an infant. Sounds like you likely have a spirited LO and that book is a godsend IMHO.
Hang in there mama! :)
~megan