My best way is to stack the coals right up to the grate, maybe even propping the grate up just a touch. After the pile burns down for a few minutes (1" or so below the grate) I cook indirect and sear at the end. I prefer medium rare most of the time but I'll take ribeyes a little higher sometimes. I'd probably start the sear when the meat is right around 100F - still super soft, maybe sear ~45 seconds per side usually with the lid off (~2-3 times per side), flipping as soon as the hot side looks juicy. I also like to use whatever wood chunks I have, usually pecan or apple.
I've done it like this on the bottom of my WSM, the 14" SJG, & the regular kettle.
>>edit: I see you used the word 'char' where I'd use crust, & then I looked at a few of my last steak posts & didn't see much of either of those
When I think I have char or crust - that always softens & the color lightens.
Here's a ribeye I dry aged for a few days:
http://tvwbb.com/showthread.php?56532-Dry-Aged-Ribeye-4-days
I've only cooked one caveman style & that was on a
quick overnight hike. I didn't care too much for that - kept picking pieces of charred wood out of them, but we used scavenged wood,,,threw them on the campfire.