Hey grandpa, did ya see my pic on the new fishfinder pt 2 link? this stuff is great. MY temp might be a few degrees off since I didn't total submerge the fishfinder but its only off by 2-3 degress, close enough for me. - Jason

I mounted mine just forward of the two scupper tubes by your feet and got a good set up. I used the closed cell foam for the frame and it works perfect in that area. The area is as far back as you can reach in the forward hatch.

Chad 

I just mounted a new one and this time I am using regular old 100% silicone.  I used the whole tube!  We'll see how this works.

Also, this is the battery I have been using for over 2 years now:

You can get it at Batteries Plus.  This battery will power the ff and a 12v boat light for at least 8 hours.  I plug it in and leave it on, take it home and charge it back up.  I've probably charged this thing over 100 times.