In cPanel for that main account, find the icon titled Disk Space Usage. Using that you might find some things on the account itself to remove. If logging is enabled on the account you can free up some real space by turning that off.
cPanel > Raw Access Logs icon > make your selection there.
EA3 logs are found at /usr/local/cpanel/logs/easy/apache/ Not sure that'll help much though. EA3 also renames and backs up the apache directory. You'd find that/those located here: /usr/local/
you may find apache.backup and apache.backup archive there. If alls well with your server's Apache setup, these could be killed.
You might login as root and check space with something like this:
this one displays free dsk space
df -h
this one displays disk usage
du -h
Maybe something useful in there somewhere.
