It might be easier to upgrade to ePO 5.0 on a new server and use the migration wizard to transfer settings.
If, of course, your old ePO server passes the migration health check.
That's what I'm contemplating doing to get from 32-bit to 64-bit.
I tried the migration wizard and had it start to migrate settings but then "roll back" after it spent 15 minutes trying to start the "new McAfee services". Have an open case with McAfee who initially referred me to KB 71078 which explains a manual method for moving from 32 bit to 64 bit. That is what I am trying know before calling McAfee tech support back.