I don't know if anyone has done something similar but this is how I will connect a cord to my heating element. I used a deep octagon box and knocked out the back to 1-in. Then I welded the box to the locknut on the element. The weld is strong enough to tighten the element in with the box.
Just thought I'd share. It was quick, cheap and looks pretty clean.
Thanks IP for the help with the pictures. I had to install a plugin for Explorer but still not working quite right. I'll keep trying.