An interesting post about Geraldton commercial FM stations in the 90s, which were the first in WA outside of Perth.
From what I read, Triple G & 98FM were competing with each other for much of the 90s.
In around 1997, both stations came under the same ownership according to this document: http://www5.austlii.edu.au/au/journals/CLCCommsUpd/1998/4.pdf
This following document dated from 1994 is worth a read, particularly detailing about commercial FM radio in Geraldton: https://ro.ecu.edu.au/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1622&context=theses_hons