Finicky kitten only eats fish-based wet food

I recently adopted a kitten and his previous owner fed him wet, which is great, but only the kind in gravy and only fish types. I'm now trying to transition him away from gravy and fish-based and he's just not having it. I've tried mixing poultry and rabbit based foods into the usual and gradually increasing the amount, but he will actually eat around the offending food (no pate here; chunky only) and leave it.

Abby ideas? I would prefer to have him eating a different type of protein, but my efforts aren't being met with much success.

Thanks!

The only thing I can suggest is to start with smaller portions of the new food.  When introducing raw, they say to use as little as 1/4 TEASPOON mixed into their existing food .  That's a teeny amount .  So I guess you could try mixing 1/4 teaspoon of something chicken flavored into his beloved fish and see if he'll eat it.   If not, just keep doing it until he gets used to the smell, etc. and see if eventually he does.  Also, even though it's chunky only, you can try kind of breaking up the chunks to be able to mix in the other food, can't you?

Another think to try is using toppers on the new food?  Does he have any favorite treats that he likes?  If so, crush those up and sprinkle over some different canned food to draw he to it.  Or use parmesan cheese (yes, from the green can!), or even tuna water poured over some chicken flavored cat food to get him started.   Or FortiFlora sprinkled on top of whatever you want him to eat.