Are both partitions full or are you having problems with just 1 partition?
I haven't tried it, but if you have a larger drive you could pull one of the mirrored drives and put in the larger drive. Let it re-mirror, remove the smaller drive and then use something like Partition Magic to resize the partition. As long as you pull a drive before that you will have a backup drive. Just a thought, but I'd see if anyone else makes any suggestions too.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.