Four-post switch in my variac?

[SoaDMTGguy]

I have a Standard Electric “Adjust-a-Volt” 500B variac. It needs a new on/off switch, and I gave one of the right size. However, the units switch closes both the positive and neutral rails, while the switch I have is only for one. Can I put this switch in and simply bypass the neutral line?

 

[rayma]

You could but it's safer to break both lines, especially if the AC outlet is wired backwards.
I once met a carpenter who built his entire house, and wired each and every outlet wrong.