My, Amnon! That sure is a mighty different (yet similar!) solution! Very smart; I never even thought about doing it that way. Just goes to show how theoretically versatile this glitch can be.

(I am however glad we covered basically the same glitches!)
Very glad you enjoyed

Oh, and I've also uploaded your solution to youtube; will link it to the OP in just a moment.
Edit: I would note that this solution would be impossible if I just used empty tiles instead of lava... or any other box instead of steel...
why did my mind put these two together?