Marcos,
This answer might be best put over on the postGIS listserv, but I will suggest a couple of strategies based on some
differingassumptions and certainties.
One certainty - it seems that you absolutely have to have some form of PostGIS installed in order to perform the
postgreSQLupgrade using pg_upgrade.
One variable - whether or not you will have to do the "hard upgrade" required by the postGIS version when doing the
standardPostgreSQL upgrade. In other words -- is the postgreSQL upgrade essentially doing the same as the "hard
upgrade"?
If YES - then install postgis 1.3.x on your 9.2.4 then use pg_upgrade, then do the pgis hard upgrade
If NO - install postgis 2.x on your 9.2.4 then use pg_upgrade
This is a very relevant case study, one that I myself will be going through very very shortly here so I am interested
tofollow your progress and assist in whatever way I might.
Regards,
r.b.