Hello Ed, Can you explain what "caulk-ins" are and where you bought yours? I am doing a similar install on my house but am using 22 guage corrugated steel. My house has a red brick veneer. Up until recently, I thought the brick was solid, but when I drilled into it the other day, I discovered it was hollow red brick, with two cells per brick. I was thinking of using a panelmate type fastener, female variety, that would go all the way through the brick and anchor into the wood 2x4 studs that are underneath. Has anyone ever done this? Thanks Joe Stewart