So if anyone reading this is interested and has the same question, here is what I have found so far having now gotten my hands on the actual boat. The Fusion control head at the rear swim deck is the MS-RA70N, which was the current model of that line when Yamaha was building the 2019 models last year. This model of the head unit has no SiriusXM ready input ability. So, I'm out of luck unless I do some sort of Aux-input. Since I am a fan of hardwiring and as much total integration as possible this is no bueno for me. Since then, within the last few months actually, Fusion released the MS-RA70NSX (SiriusXM ready). I called Fusion customer service directly today. This newer version is the exact same control head, completely, except it replaced the spot for the "ACC" plug in the back with an "XSM Tuner" plug-in. The new head unit is ONLY compatible with the SiriusXM SXV300 tuner, yet the representative said that they highly recommend using a "Marine" quality antenna instead of the automotive model antenna that usually comes with SXV300 Tuner. The discussion of these antennas is already a part of a few other threads on here so I will not repeat all those. With this all said, if you really want seamless integration (like me) and are willing to pay for the new control head ($250-$300), you can literally just pull the stock receiver out, unplug the connections, plug the new one in (with the new tuner plugged in of course), and band-a-bing, you're in business. No cutting, no drilling, and no rewiring.
Now on to looking at VHF radios, that Lowrance Link-9 looks purdy nice.
Marine Entertainment System with Bluetooth & NMEA 2000 | Fusion Entertainment
Marine Entertainment System with NMEA 2000 & SiriusXM-Ready™ | Fusion Entertainment
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