Gluten will steep out from all grains.
As was pointed out in another thread, millet & buckwheat can both be malted and roasted to replace most specialty grains. I think this would be the most practical approach. Use sorgum, GF-rice syrup and molasses as the base sugars. The mrgoodbeer link discusses the malting process, which is identical to the barley malting process. Palmer's book discusses toasting & roasting to achieve various specialties.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
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