There never was a 'memorable race win' of that kind of stature for an FE or FC...
Bruce McPhee had the most 'memorable' car in the field in the Appendix J days, Lou Kingsley in the pre-Appendix J days, while Bob Holden got the one that Repco built up and had been raced by Stan Jones.
Others who raced them included John Raeburn, Alan Dewhurst and Fred Rheinberger. Later in the Sports Sedan days there were many. Chris Strode had one, Barry Sharp has been mentioned, I think his went on to Bill Warner.
The problem is that the FE and FC were from a period when tintop racing wasn't big. The Armstrong 500 started in 1960 and the FB was already well and truly out then, so there was never a serious endurance race for production cars in their time. In other racing they were always considered to be too heavy alongside the early models, but blokes like McPhee were always willing to try to prove a point.
Alongside the 1957 WATCC for Lou Kingsley, Bob Holden won the 1958 Victorian Saloon Car Championship on October 19th at Fisherman's Bend. Bob didn't quite get the Repco car, but got all the running gear from it given to him by Charlie Dean and put it into an ex-taxi. I figure the changeover was between April and December 1957, as that is when the Repco car last appeared and the Holden Holden first appeared.