I have a blank 2"~ 2 1/8"" opening on my dash.

http://tinyurl.com/abnwu

I just bought the boat (as of tomorrow assuming a good sea trial). It does
not have a compass or depth sounder. I can put either in that spot (
http://www.marine.com/product_info.php/products_id/653 or
http://www.westmarine.com/images/full/530298.jpg ) but can also leave the
hole blank, mounting a surface mount compass and moderately priced fish
finder with depth sounder on top of the dash.

Pricing is comparable (a bit higher on dash surface mounts) although the
units installed on top of the dash would be easier to read while at the helm
and will offer (as in the case of the fish finder) more data on a larger
surface.

What are your ideas? I am leaning toward the larger units mounted on top of
the dash.