Mick,
ACE is correct, anyone is welcome to join the FE-FC HCC of NSW if they have an interest in the preservation and restoration of them, which doesn't mean you have to own one. At one stage when I was President I only had an FC reduced to component parts and went to meetings and runs in my company supplied Falcon
So turning up in an EK would be a mild sin in comparison to that! It's quite routine to have a variety of other models as well as modern stuff participating in our events, and we welcome that. The club is above all a social group with a common interest.
Having said all that, you should make it your business to get along to one of the FB-EK Club's meetings. You might find participation there to be to your advantage too. I know a number of guys from that club participate on this forum. If your EK is stock maybe the Southern Sydney Early Holden Club is worth checking out too, since you live in that area. They cater for all grey-powered Holdens.
After all, there's no law saying you can only belong to one club!
cheers
RET