trouble pulling subject into rename of .eml file in finder

I have a finder folder in which I'm trying to rename eml files. I'm able to pull the date received but can't get the "subject" into the rename. Please see the following for my approach:
https://www.dropbox.com/s/vcskgrin0lnfe ... 2.png?dl=0
https://www.dropbox.com/s/dj3zggp8rh0oy ... 1.png?dl=0
Thanks for any help.
~Chuck
https://www.dropbox.com/s/vcskgrin0lnfe ... 2.png?dl=0
https://www.dropbox.com/s/dj3zggp8rh0oy ... 1.png?dl=0
Thanks for any help.
~Chuck