If it is a Nelson, then probably it takes a Nelson plug, not a "Turbo" plug.
Nelson plug is bigger in OD than a regular or a Turbo, so the head button can't be simply drilled out to take a regular plug.

That aside, the timing on the Nelson is probably not going to be optimal for a typical sport model.
The fact that it uses a non-standard plug tells you that it was designed for making horsepower.

I could be wrong, but not sure Henry ever made a "sport" version of the 40, just the Quickie 500 version.

It is possible that a PA40 head button might fit the Nelson 40 and take a regular plug. Check with Randy Smith to see if that is the case, and if he has any spares.

If you do put it on a Magician , be sure to take video

I presume you've converted your Ferrari to a minivan to haul the Magician to the field.