Mine also doubles as a grill .
I just bolted 3 steel adjustable shelf bracket (standards) equidistant around the inside ....cut the shelf supports short enough so that you can maneuver the fire basket up or down between them but long enough to support the basket securely when you have raised (or lowered ) it to the desired height .
Got some calf moose ribs on right now....in the second stage of the 3.2.1 method ....hope they turn out as good as the pork ribs that i did last weekend....
Thanks for all the good ideas on this site.
I built mine about 2 years ago....found a grill last summer did up a fattie and some ribs ...getting better