Don,
From my understanding of a lever fill, the lever (part of the pen body) pushes a bar (J bar) that squeezes a sac.
I have not heard of a "converter" that has a lever. another version is the aeromatic converter which is like this. It's a sac inside a converter that has a bar that you squeeze to fill. So your options, that i'm aware of, are twist, slide, or squeeze.