Considering ez complete

Hi everyone! I'm considering switching my cat over from canned food to homemade raw using EZ complete but I'm confused with the prep and amount to feed.

I've looked around and came upon a website that recomends "So, if your cat eats 6 oz of canned food per day, your cat will likely eat 3.6 to 4.5 ounces of homemade food to maintain current weight" (https://www.rawfeedingforibdcats.org/the-cost-of-feeding-ezcomplete.html).

I'm assuming that meant just the meat weight not including the powder or water so the total weight would be 6oz(4oz meat, 2oz water)+powder weight?

And I'll have to take calories into account so if my cat eats 200cal/day she would need 4oz beef/day(7.5lbs/month). But if she eats chicken which is lower calorie then she would need more lbs and powder.

Please correct me if anything is wrong. And for prep is it more efficient to mix water, powder and meat beforehand then portion or to just mix meat and powder then portion(warm water when feeding so it isn't cold)? Any other tips would be appreciated!