i have this transducer in my boat! i just found a clear spot as far back as i could clear of all chimes or anything that could cause air bubbles! i had already had a trans in the hull so i new my spot would be ok! then drilled a pilot hole then used the hole saw to drill the hole! make sure you check the transducer after a few trips as mine came lose and spun around a little causing a slight leak! make sure you check which direction the trans is meant to be facing!

could try this - http://fishwrecked.com/forum/cruise-craft-575-585-thru-hull-50b-9b-transducer-install

So I have got the spot picked. I just have to try and find a suitable hole saw for the job. What sealant did you use? Do you have any problems with it leaking any more? And how tight do you have to do up the thread as mine is in an awkward spot to get any leverage on it. I just had a look at the existing wiring, the bloke that owned this before me has wires going EVERYWHERE!!! Hooked up to an NMEA unit with wires connected to other wires leading to who knows where...That should be fun. And he hasnt colour coded much of it, all the wires are connected to other colours. If I dont melt something it will be a miracle.

the hole saw i had was just a smidgen too small so i had to route it out with a griding bit! i used marine sikaflex! no it hasnt moved since! mine is in an awkward spot too! as tight as you can then just check it again! if i was you i would be ripping the wiring out and starting again! its not worth the heart ache getting out there and something not working! or worse still something catching fire!

matt wrong trans! but good link he done a bloody good job