I made the wine that Yooper posted (Jack Keller's) last year and I really enjoyed it. I used the steeping method and thought it had a good flavor. I could see it being easily overwhelmed in a beer, so I would definitely go with something simple grain wise. I think if I were to do it personally, that I would make a gallon of the tea. Then I would brew, aiming for 4 gallons of wort instead of the usual 5, and then top up with the gallon of tea. As a side note, I let my tea sit for 2 days in the fridge instead of a few hours. The flavor got noticeably stronger, but I didn't pick up any extra astringency or anything negative.