Well, just to update everyone, I did get her all cleaned up using regular ole Spray & Wipe. Turns out whatever I used for protection last year did a really good job of allowing me to just wipe it clean.
And yes - it's a Merc. I went ahead and had the oiler taken off and did my own premix starting with this fill up. It's amazing the peace of mind I had not having to worry about the yellow light flashing when I'm miles away from the ramp.
And, if anyone is interested, we did well fishing yesterday. The fish are definitely biting.