Fourth item from the field - probably a plow point.

I'm in the midst of cleaning this object. It may be part of the same plow as this other unsolved - http://www.collectorsweekly.com/stories/123629-third-item-from-the-field--would-love-t?in=unsolved-mysteries

Ok, see the partially cleaned image. I cannot read all of the letters, but ones I think I can read are: "ILLU" the next letter might be an R or P or F, then the next might be an S. However those last two letters are very questionable. I will be trying to clean more of the rust off, but thought I'd post this in case some learned plow expert might know what this is. I wondered if I have the two pieces fitting together like they should go? The last photo shows some unintelligible figures that are to the right of those other letters. Any plow experts out there ? Help !!