OK, I suggested you start the bike and spray some Gumout or other spray into that carb which will tell you if it is the carb. I think you passed that tip by and focused on compression for some reason.
The 78 pumper carbs do not have clips as we all know at this point. The 78 carbs also have actual mixture screws and not air screws, so you actually enrich the gas mixture not restrict the air. Bottom line, you probably don't have to swap around needles.
I do not wish to be unkind. You are going to confuse yourself trying to perform needle swaps from other carbs. At this point you do not have the expertise to perform these things.
If the carbs are off the bike put them on a table and look at them. You will see how they are built. Just look at them for a few minutes.
The main thing you should focus on is getting them to function normally, forget tweaking and modifications, just get them operating properly.
You need to pull the idle jets, get a pliers and just lightly grab the jet, a slight wiggle and a twist and they will pull out. If the brass gets a scratch no proble, you just don't want to make them oval.
A thin piece of copper wire from a lamp cord or speaker wire will loosen the crap and you can flush it out. They are all blocked from the MBTE they had in the gas at one point.
Fix your accel pump and get that working. Once you have the carbs at a proper base line function, and get the motor running well. You can then fiddle with tweaks and refinements. Unless you have have the basics sorted out, you can't refine anything.
I am running 120s with a stock air box and have no serious plug fouling, so you may have to go bigger later on, for now stick with what you have and make it work well.
You have a lot of well intentioned people here who know what they are doing, but they will lead you in circles unknowingly. You do not know enough yet to do those things.
