ford doesn,t run right

Working on a 8n .belongs to my grand daughter. When I got it the number one cylinder was dead. took a compression reading it was fifty lower that the other three.Pulled the head and changed the rings on that cylinder. Found some one had over hauled the motor .It was a complete over haul . Bearings and rings looks like the head had been trued up. They put chrome rings in. I don't think they have worn in quite yet. Since I changed the rings the compression is the same as the other cylinders.
Now the carb float doesn't work right it either doesn't let any fuel in or it runs all the time and floods it out. I bought a new carb it was only about forty dollars and wasn't worth that .The drain plug won't seal I think the casting is cracked and the float doesn't work it won't shut off also some of the seats were stripped out. So I bought a repair kit for the original carb. It had a different needle and seat . It seems like the float isn't going up and down what ever position it is in when I install it is where it stays. I have gas to the carb. So I bought another float seems to do the same thing. I bought another kit that had a needle and seat like the original. The needle doesn't seem to drop. or if I install it down it won't shut off pretty much the same as the other kit Haven't worked on a flat head for a long time wouldn't be working on this one if it wasn't my grand daughters.
Any help would be greatly appreciated.

Pa Farthing, there is a forum just for the N series tractors like your grand daughters just below this one. There are a several very knowledgeable guys that hang out there. They should have some good suggestions.

I have bought 2/3 aftermarket carbs. they all have worked fine. you need to send the one back and get another one. a lot of people like me thinks they can rebuild a carb but really cant. I've learned my lesson on that. make sure you are not restricted in your supply line to carb. you might also spray some wd-45 in the inlet of the carb. it actually lubricates the needle valve. might help some. good luck