Esmith,
I'm running 1" Leupold medium rings on all 3 of my CL bbls, MC stock for two and straight for the other. The CL makes it way higher than your "bird" bbl obviously, but I really haven't had a hard time shooting the gun with a straight comb this way. Took some IA whitetails with it and never really felt a disadvantage with a looser cheek weld. The MC stocks definitely give you a more solid cheek weld with the the higher CL mount.
You may want to check into the cheek pads that wrap around the stock.
To answer your question, go as low as you can get away with clearance.
