Mixed into a large outdoor bed is different than inside a container. If your plants begin twisting just back off on it. Manure or any kind of organic fertilizer won't burn plants severely like synth nutes do. Cow manure is slower release than chicken shit so you can add a lot more without worrying about N burn as much.
TBH I don't even really measure what I add with any kind of accuracy myself. I just kind of eyeball what I add to my mix by handfuls.....that is the quantity of dry amendment I can grasp on to without it falling through my fingers I consider a handful which measured out is about a cup to a cup & 1/2. If you want exact ratios plus soil and tea recipes go buy this book:
https://g.co/kgs/P7sYGX
Could be the best $20 you ever spent. Was for me.
To help answer your Q I can tell you what I do is add in a few "handfuls" of chicken manure to my recycling mix. I add about 3 lbs of cow manure or 1/4 of a 15 lb bag plus a handful each of all the other dry amendments and as much EWC as I can muster to a recycling soil bin which holds about 40+ gal. I let it set for a month after that to let it all cook in.
When I build the final size pots that are intended to feed plants through bloom phase to harvest I add one handful of chic and 3 handfuls of cow manure to 3 rusty shovel-fulls of recycled mix in the bottom of a 10g smartpot. I also push in 2 jobes spikes which feeds for like 60 days. This is all in the book btw. So I add fertilizer to the mix globally and I add some extra to each of my final size pots for bloom phase. Plus EWC which is just as important. I still give teas every so often but I'm not as regimented as I used to be.
AACTs help maintain high levels of microbial activity which makes your plants supernaturally healthy and green. You don't use them to feed plants as much as you use them to feed the soil. You will need AACTs more at the start of your organic adventure than you will once your established mix is uber rich in microbial life.
Yes you can top dress but you don't have to scoop out the top layer just layer it on top or do a full transplant to fresh mix. If you top dress I would mix the manure in with some soil first though to cut it down a bit and try to lay it all on the outside edge perimeter of your container so it's not right on top of any exposed roots. Add in some kelp meal too if you can. Hard to say if that will keep em green all the way to finish but if that's your aim push in 2 jobes AP organic spikes; one in each side of the container 180 deg apart from each other. Use a clean no chlorinated water source and give an AACT every 2-3 weeks. Water only after week 6. Hope that helps you & sorry for the longass reply