To answer your questions in reverse - donations to yatzr go to him, donations to the GUESS reports go to me. If you visit any world's home page (ex: rockne.gdreports.com) you'll see a button for donations to the GUESS reports.
Based on my question to oriole in the dev chat - it appears to me that the Tackle and Guard / Center designations don't really have much impact on the way the OL wokrs. It's really just another way to set your depth charts. Honestly, I am probably going to ignore those designations and instead go for Run Blocking and Pass Blocking ratings.