Global firewall templates

I love the global firewall templates. It allows me to have consistent policies across my clients. It's a shame you can't apply multiple templates, but imagine this has the potential to cause conflicts. I just have one global template applying to all customers.

I now have a need to create a specific template for a customer that has 24 Sophos firewalls. I don't really want to start a brand new template from scratch. How can I clone the existing master template, or at least export/import the settings from that template in to a new one?