I like to soak the carb in some diesel fuel first. Warmer would be better but I don't know how safe it would be to try and warm up some diesel. Usually, the soak in the diesel would be a preliminary soak, then hit it with some high pressure water. Then, if you have a large crock pot or an electric roasting pan (they sell them at walmart) you could fill that with a mixture of water and Gunk-purple cleaner with the heat turned on but not too hot, maybe 175 degrees. you could mix in a bit of dawn dish soap with it also to help with the last of the grease buildup. Next would be the soak in the "carb cleaner bucket" like berrymans or gunk brand. Problem is the carb cleaner bucket cleaners are not what they used to be. Actually, the cans of spray carb cleaner work fairly good if the carb is not too dirty. You got too be careful with anything with strong acids as they will entirely remove any of the plating eventually. A bottle of "the works" toilet bowl cleaner mixed into some water in a bucket, barely covering the carb, will eat every single bit of rust, grease and carbon buildup BUT it will eat the plating right off til the carb is just a plain grey color.(probably would eat right through the carb if left in there long enough) Also the fumes are just killer, use caution and do this one outside IF you want to try this. Just horrible fumes that just have to be bad for you.
Of course, you could send the various carb parts (main, top casting etc) to either a plater or to someone like Cliff that would put the parts into an ultrasonic cleaner, that is probably the bbest method. I haven't tried the pine-sol yet but from what I have seen on the net, it looks like that method might have some good results.