HELP - need way to restore only blobs

I recently posted a similar message but left some key info out:

I migrated my database from 7.3 to 7.4 this weekend using the pg_dumpall
tool which I now realize does not capture blobs.

I now need to move only the blob data to the 7.4 database.
The problem with redoing the dump with pg_dump -b is the database is now
in production and writing over the top of changes to the database is not
exceptable. The blob data is very static so if there was some way to
copy the physical files from disk and modify some records in the system
tables to properly locate the blob records that would be best. Another
option I was looking at was to restore the archived database with the
blobs intact and then restore the production version over the top
without destroying the blob data.

All suggestions welcome, I'm dying here.

--
Warren Little
Senior Vice President
Secondary Marketing
Security Lending Wholesale, LC
www.securitylending.com
Tel: 866-369-7763
Fax: 866-849-8082