Updating a compatibility mode 80 database for SQL Server 2014
How about spinning up a SQL Server 2000 or 2005 server.  Then script out the 80 database objects and create them on the earlier version SQL Server.  

Then run the SQL Server 2008 R2 upgrade advisor to collect the 2000 and 2005 errors that might exist. Once you fixed those issues on 2008 R2, then you can run the 2014 Upgrade Advisor.