Half fire ring

To maximize your height inside you will need to place platesetter feet up and place your turkey in a drip pan on your platesetter.  I would place tin foil rolled into 3/4" balls under drip pan to get air under it to salvage your dripping if you want to make gravy.  Place the bird horizontal (breast up) on a v-rack or place celery stalks in the drip pan and place the bird on them.  You can always pull out the thermometer and watch the temps with a Thermapen if you have one.

How big a bird are you trying to do?  

I use and like this recipe, it makes great gravy as well as very tasty Bird.

http://www.nakedwhiz.com/madmaxturkey.htm

Good luck, have a nice holiday.