I just replaced the existing two burner electric stove top on our Mainship Pilot 34 with a two burner induction stove top. I used this one: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
It fit nicely into the existing space of the old one. I had to lengthen the cutout about 3" and it was a 1/16" too short to cover the existing cutout on the sides, but I ran a bead of caulk on the sides to cover it.
The old burner is attached with a bracket that you remove from underneath after pulling out the fridge. With the bracket removed the burner assembly is only held in place with caulk so push up from below (and use a putty knife to break the seal around the edges) and it will come off.
The existing circuit is 20 amp 12 gauge and would trip the breaker with both burners on high. This one is designed to limit the input current to 15 amps. If one burner is on it can draw 15 but if both are one the power is automatically split between the two to limit it to 15. Wiring was simple- just cut off the plug on the supplied cord and strip it and butt connect it in place of the existing splice, all in an electrical box of course.
Induction is much more efficient at transferring heat to the cookware than the old burners, so 15 amps probably gives more cooking heat than the old 20A one.
We bought a new small pot and skillet to use with the stove top. Those will cover all of our boat cooking needs.
Here is a pic of the unit: