If it isn't already pre wired, the new induction cooktop will need a new dedicated 220v/240v line run to it from your circuit breaker panel. That assumes there is room for the additional breaker the cooktop requires in the panel.
The next hurdle: will a 36" unit easily go into the space now occupied by the present cooktop or is some reworking or a new counter involved?
A little secret: need some more temp prep space sometimes before cooking starts? Just lay a Silpat over the part of the induction cooktop surface not in use at the moment to protect it.

This post was edited by laat2 on Mon, Sep 29, 14 at 10:44

You can also use the cooktop for extra counter space- I just put a silicone mat on top when I need space

The key is burner configuration on the 30 or 36

Yes, double check for correct wiring and the correct amperage for the cooktop you want. They range from 30-50 amp requirements. I was very lucky that someone came out with a cooktop that required only 30 amps, since that's what I had!

I went from a 36" radiant to a 31" induction (Bosch) and don't miss the cooktop space, at all. For what it's worth, I cook at least one meal a day for a family of 5. So far, the most hobs in use at one time have been 3.

I replaced the countertop, so didn't have to work with the existing cut-out.

Love my cooktop and love how much cooler my kitchen is during meal prep! The hob configuration works very well for me, but that isn't a big deal if you go with Flexinduction.