Ok, are you having a problem with 1/4" for the FB? I would at least use 1/4" for the top of the FB and taking it into the CC as the BP. But you can do it your way. I have seen FBs warped and I believe 1/4" is where that seems to stop. I'm not trying to be a stick in the mud, just trying to share experiences.
Making memories.
Current Smokers: Backyard RF Offset and Hybrid RF Offset trailer rig with Cowboy cooker and fish fryer, always room for more........