Sure, where are you located? If you're not too far from Sodus Point we can handle that. I have a great installer, and I understand the products. It might be easier to chat. You can call me at the marina.
One of my distributors has the dual spectrum in stock. I can drop ship it to you. They list for $3900. I can sell it for $3800+tax if you'd like. If interested give me a call at Krenzer Marine.
I do it all the time in my Lund, but without a kicker or using your main engine to propel the boat the battery will last a couple of hours at most. I use the kicker to get me close to the speed I want and then put my Minn Kota prop speed at 4-4.5 to give me good steerage.
There are a few on the lake. I store a few at Krezner Marine. They are nice boats, but other than looking at them I have no experience fishing one. If you'd like I can ask those guys if they'd take your phone call?
I installed a new one on a 27' Robalo two weeks ago. They have definitely made some improvements. Which model are you looking for? I can check availability, and drop ship it.
Make sure the power wire going to the pump isn't run with your transducer wire. We had a an install and found out the hard way. If every time your AP pump runs you get interference chances are those two wires are run together. Separate them and you should be fine.
The Striker series isn't a great series for Great Lakes fishing. The GT52HW transducer it comes with has high wide CHIRP sonar and has a power rating of 250 W, which is low. That transducer puts out a sonar cone angle that's < 24*.
The cone angle of the Airmar I mentioned above is 45* and has a power rating of 600w. These transducers have been staples on the Great Lakes for many years. You can get them in transom or thru-hull models. For your boat I'd recommend a transom mount, which is the P66. Since you like Garmin the series just above the Striker series would be the way to go. I have 7" ECHOMAP units in stock for $440. I can pair it with the Airmar P66 for $160. If you wanted to save a few bucks you could also purchase a Garmin Dual Beam (77/200) transom mount transducer for $80 and still be ahead of the Striker you mentioned. Both transducers I mentioned are traditional sonar transducers and no fancy side/down imaging, which isn't needed for trolling the Great Lakes.
Whatever you do don't settle for the packaged transducer. They typically aren't great for trolling open water. Add an Airmar P66 to whatever you buy and you will be very happy. If you have specific questions give me a shout.
We have, but it's not something we do often. I put a heavy duty snap on the back of the probe, and an Offshore OR-16 clip on the front. This is also how I attach the Smart troll to a slide diver.
We have a Lake Ontario Charter Boat Association meeting the first Tuesday of every month (there's one tonight). It's held at 7pm in the upstairs portion of the Irondequoit Fish & Game club. I think it would be a great place for you to learn about the fishery, charter boat industry, and meet local captains who may need your services.