Ice, You need the tach signal generator. It's very easy to install, but you do have to run a few wires to your alt.
Ray, I hear what your saying. I didn't think it was very hard to adjust the radio either. The problem is, I don't always drive my boat. And I can't even count the times I've had to remind people to turn the radio up. And it's even worse when I'm riding.
In a big way, I got it for the same reason I got my 1st Perfect Pass. I could hold speed just fine, but I always got a crappy pull, because others couldn't hold the speed.
So now I always have tunes. I was actually giggling the first time I rode. Every time the volume came up on it own was like a little slice of heaven.