So I've got another thing to hand of to my team while I'm out of town this week =)
Luckily I think we can just change the GPO for the IT testing computers and if nothing breaks for a few days roll it out to the whole company, I'll have to check if the GPO enabled version of Firefox we use has an option for disabling SSLv3, it's really only used for one internal app, but it's better to be thorough.