Did pg_dumpall and imported, NEED TO START OVER

I'm preparing to upgrade and am practicing.
I'm using v7.4
I created a blank .7.4 to import a pg_dumpall into. (Also a v8.2 to
upgrade to.)

The encoding was wrong and I have a lot of:
psql:/tmp/cluster_pg_dumpall.txt:4382: ERROR: invalid byte
sequence for encoding "UTF8": 0x91
HINT: This error can also happen if the byte sequence does not
match the encoding expected by the server, which is controlled by
"client_encoding".
CONTEXT: COPY brokenbin, line 443

Do I have to back out and start over?

drop database?
Or clear out and start over w/ a new install?

If the latter, what do I drop before I can start over w/ an `initdb -
E SQL_ASCII`

THANKS!
Ralph Smith
smithrn(at)u(dot)washington(dot)edu
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