Dual quads versus big hammer!!!...

just an opinion. The secondary air doors are opening too quickly need to slow them down, keep tightening until stumble goes away . You could keep throwing larger squirters at it when the originals were probably ok.The original jets were probably close . The plugs look and probably are too cold as 318 said , thats why there not clean and hard to read .

I doubt the jets are close. He doubled the jet area and didn't double the flow.

You can tighten up the doors so they never open. I doubt the bog goes away. If he is having a standoff issue, the secondary air valves not opening won't help that.