6.34 security when closed

We currently use a heavily modified 6.34 on our site. I want to upgrade because of the security considerations but it appears the effort to do that is going to be rather monstrous, especially to come through to 7.9.

Unless someone has a magic set of SQL to upgrade a 6.34 SQL DB to 7.9 I'm looking at just creating a new database, modifying 7.9 ASP to produce output closely like my existing site and then close the 6.34 database to new posts/pms/whatever.

I'll then combine the searches (probably just a frontpage to allow searches on both the new and old DBs).

The question is: I know a lot of security work has gone in since 6.34. Will it be secure as a closed (but viewable) forum?

Alternatively, does anyone have the magic conversion script?

Cheers,

Andrew B Davidson
http://www.hypostasis.info
peer support for type 1 diabetics, friends, family and others