Thornbill ?

Hi

At sydney olympic park i saw some silvereyes in these casuarinas, then they were joined by some little yellow birds about the same size as the silver eyes.  At the time i thought the yellow birds were all the same species, but i did notice at least two had solid orangish beaks.

Looking at the pics later, I think there were actually yellow thornbills and greenfinches together (both new species for me - incidentally at the same time there was also a scarlett honey eater in the same casuarinas which is the first one i had seen at SOP!). 

Yellow Thornbill?

Yellow Thornbills?

European Greenfinch?

Not sure which this is the rear view of 

I would appreciate any help with these ids.

Thanks

WD