Kittens, at least mine, are allowed to eat all they want at 3-5 meals a day. No food is left for them in between feedings, because from what I have found, that is actually hard on their bodies.
Here is what I do. I portion the food up into ziplocs and put 20 oz in each ziploc. This is what I do per ziploc:
12 ounces meat (beef heart, beef, chicken heart, chicken gizzards, chicken meat, pork, pork heart, pork tongue, turkey, etc. Any meat from an herbivorous animal.
6 ounces bone-in chicken (I buy whole chickens from the grocery store, cut them up, and smash the bigger bone pieces with a hammer, so that kittens can easily eat it)
1 oz liver (from any herbivourus animal...sorry, I am a bad speller!)
1 oz "other secreting organ (thymus, pancreas, reproductive organs, kidney, brain)
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You would be suprised how big of pieces kittens can tackle. Personally, when Morey and Mitch were around a month old, they were able to eat pieces of meat that were twice as big as their heads.
Fish: I very rarely feed fish. Mine get a sardine each week, for the omega-3 content. Else, I use salmon oil capsules, meant for people, and give the cats 1-2 of those each week.
I'll post more info later

Not much time right now...
I'm glad that it is nice out today! Wednesday night, I was feeding calves outside, and came home drenched. Thursday it was hailing for a while when I was outside feeding calves. Hopefully, it stays nice out, so I don't have to deal with rain/hail tonight while working!