Newbie needs help with fish finder install

Hello NWKA.  I am a newbie to the forum I used this great resource to help me pick out my new Ocean Kayak Angler 13'.  Thank you for all the posts about gear.

I have been fishin my whole life but I am new to the kayak side.  I took my Kayak out the other day at Fay Bainbridge State Park for it's maiden voyage and was lucky enough to snag a dinner sized clipped silver.  I am hooked on the experience.

I currently have my 385ci fishfinder sitting on the floor of my apartment and I want to put it together. I want to do it the right way the first time and I am hoping this forum can help.  Can anyone point me to the right post about how to install and drill the right way.  I have never installed on a kayak, much less a fish finder.  I want to make sure it stays water tight and is snug. 

I have a through the hull transponder so that side of it shouldn't be an issue.  I have the OK Angler with the fish finder shield and I am curious about the best way to run the wires from this spot up to the battery.  Thanks for any help!

I mounted a FF/GPS on my T13 as described at the link below.  Links are at the bottom of the page.

http://www.demonick.com/kayak/

The RAM Adapter Post I used fits the Scotty Deck Mount too loosely.  The one change I would make to the FF/GPS mount is to use a RAM wedge mount, but first I would verify the RAM Wedge Mount fit the Scotty Deck Mount.
http://kayakfishinggear.com/rap-354-ramwedgemountwith112ball-fitsscottyandhobie.aspx