Piece of cake. I started in a bog stock KE25 ..... errrr... a number of years ago.
I can't see you hurting it, I've literally done over a hundred of these things, and if you're sensible about things, all will be good.
While you're there, drop into the autocross track and say gday, I'll be there tomorrow with my red 55.
Dude, you won't look like a fool, everyone has to start somewhere, and the people at Holden Club are really helpful and friendly.
Don't worry, you'll have a fat time.
R