It took me about 6 months with it in my shop before I got the guts to drill a 2" hole through the hull but one afternoon last September I said it must be done. I started by sanding the hull area down to gel coat, measured once , twice maybe three times. I drilled an 1/8" hole to verify that it was exactly where it should be, my hole wasn't but the pilot hole remained in the 2" footprint of the plug to be removed. It is always a great idea to coat the raw edge of the glass with resin or epoxy prior to the 5200. Cutting and milling the bock wasn't that hard. I set the band saw table to the angle with a fence cut the block the made it perfectly flat with a belt sander mounted upside down in the bench vise. It is not possible to install the unit without someone to hole it up while the other installs the nut on the inside.
The location is as high up and as far forward as i could get it with the fairing block on the inside.
Good news is that it performs better than any transom mounted or transducer glued inside the bilge. I will never regret doing it unless the unit fails and needs to be removed. The boat is still covered or I would sent inside pictures.
Good luck and take your time, dry fit it several times, geting the block right before appliying the 5200.
