I'd guess that ANY depth/fishfinder could be mounted on a flat, shiny
surface with double-backed tape. Heck, they hung some humongous vertical
mirrors here in my house with that thick, black, sticky tape.

I have no idea how hard it would be to get the finder up when you wanted to
get rid of or change it, but , again, they REMOVED some of those mirrors to
re-cut them with a thin piece of piano wire. Have at it and tell us how it
goes.

As far as "easy to read" ...some of the units provide two font sizes as a
choice. I have a very inexpensive Eagle depth finder that has that option.
It cost less than $80.00 locally. RichG