This blog contains experience gained over the years of implementing (and de-implementing) large scale IT applications/software.

Oracle Doc: EBS R12 Upgrade/Patch Forms and Reports

There’s a nice Oracle doc on how to upgrade the Oracle AS 10g Forms & Reports component of an Oracle EBS R12 instance:
Upgrading OracleAS 10g Forms and Reports in Oracle E-Business Suite Release 12 [ID 437878.1]
Once you’ve read it, you’ll realise what a mammoth task it is.
It’s interesting that out-of-the-box, the Forms & Reports upgrades don’t work with EBS, you need the interoperability patches to be installed ontop.