Not knowing the exact amp meter installed in your panel I can't say for sure, but.
Most of those meters are set up for CTs (current transformer) to feed them,
not as feed through current meters.
The CTs are bought for the meter scaling and will often provide a 0 to 5 volt signal for 0 to full scale.
So you can put the CT around any single hot leg and wire the leads back to the Current meter.
Good point about CTs.
Interesting characteristic on those coils PopG.
Rgds, D.