I agree with Kingfisher and DB: flame at the height of the rack. 
Tips:
--Stockpile a LOT of small wood. Keep the fire as consistent as possible.  I like the old "tepee" style of fire for baking.
--Rotate the pan regularly so the food is heated consistently.  Mark the pan somehow, so you know how much to rotate.   
-- Spend some time creating a nice level surface to sit your oven on.  Makes everything else easier -- less chance of tipping disasters, for example. 
-- I agree with KF again, the box cakes, brownies, etc are good, and eggs make them even better.  I've used powdered eggs with success.
-- Pay attention!  You really can't just wander off and think the food will take care of itself.  I find this to be a fun, but high maintenance exercise.  You gotta stick around and tend to things. 

I find reflector ovens fun to bring: light, easy to pack, and nice to set up if you're in place for a few days. 

Enjoy!

prouboy

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