The two meters I want to replace are in the same block column but there is a big void in the block. Im aftaid there won't be any secure way to anchor them once I get the old ones out. The old ones are 10x15 and the new ones are 13.5x17. The column they are mounted in is 32" across. I took a picture from the attic looking down to give you an idea of what I'm talking about. Any ideas are appreciated.