Changing data graphic default size & font

[Physicsmom]

This may be a common question - if so I apologize, but I can't find the answer!

How do I change the default size of a custom data graphic? (It current
fills a rather small box) And on a related note - how do I change the font
type and size without individually selecting each text item, for each
graphic?

(I'm trying to create a 64" tall poster with multiple graphics - and Ariel
8pt isn't cutting it)

Thanks!