This document has now grown to a 51 page tutorial. Comments and corrections are requested.
I am providing a free addin QualifyVBACode. It takes the VBProject in a workbook and qualifies the xl constants with their enum types, and prefixes ones like ActiveSheet with Application. The search/replace strings are in a XML key/value config file that you can edit. Of course, please read the ReadMe.txt file first after unzipping this (XLL, DNA, DLL, CONFIG) :