Toshi
Uh Oh! A correction is needed. This is interesting.
I would mark the original instruction sheet (in the step where the error is) "Refer to 'CORRECTION" sheet" in red ink, and on the correction sheet "Follow these instructions" or something akin to that, again in red ink.
It's what I do, especially with instruction sheets that are just drawings with no written instructions, and also because I'm always having to add detail or something. So I take notes on my instructions with different-colored ink. Black is for general construction, blue ink is for painting notes (especially since so many of today's instructions show simply "A" for what color to paint the part, so you have to keep referring to the chart--"Okay, A is gloss aircraft gray"). And red means, "Be careful here!"
Hope you feel better!