At idle, generally not mains.
I used to do a lot with those, generally threw them away (look like old Holleys on Vegas and Pintos).
Idle jets too big can do that, but generally not that fast.
If the mixture control actually drops the idle down when you screw them in, mains aren't the problem at idle.
When idling (and I know it won't), would have been handy to know if raw fuel was spilling down the throat.
Electrical:
If the spark is insufficient for the job, it will load up and die with wet plugs.
New coil, you say, but always remember rule 1 of auto repair:
"Just because it's a new part doesn't mean it's a good part".
Have you actually checked spark now, with it DOA?
Do NOT pull the plugs and lay them on the block and crank or you wil have a huge flamethrower with the cylinders loaded up with raw gas.