It seems I have (more or less) the same issue as the OP. The dpkg -l command returns nothing so I guess I don't have the generic package either.

But running the apt-get on the "mp-fremantle-* packages wants to download and upgrade 991 packages, for a total of 60 MB.

I'm a bit surprised there. I can't see any reference to PR1.3 in the names, so why are they now appearing?

Is this a partial re-install of PR1.2 due to the metapackage dependency list or the actual upgrade to PR1.3 ?

The actual PR1.3 install I would like to postpone till multiboot-n900 and NITdroid are PR1.3 compatible, maybe (re)using the new u-boot method.
I just want to make it clean enough so things go smoother later on. I have already removed all libgles dependent apps and all conflicting apps other people have reported.

Any people in the same situation, also having this huge list of packages to download just to satisfy the meta-package ? Can I safely install them?

I'm also using Titan's power kernel, basically all is working nicely as it is but I fear a lot of applications will be updated to work with PR1.3 and break in PR1.2 as a consequence. So I might be stuck with older, not supported versions of the software.

Just threading careful here, too many things have been installed/customized to have it to redo it all again after a full reflash...

Thanks.