Spacezi, I am in pretty much the same situation, but was having a little trouble with this as its the first time I've flashed some hardware.
I went over to http://binflash.cdfreaks.com/
and downloaded the gui version. Backup was created just fine.
Then I downloaded the 203D dell version and unzipped it.
In the readme it says to run this in a non-windows command prompt, but you said "and just ran the file 6500FAST in windows as per the readme file included " How did you do this / what command did you use? I tried opening a command prompt in windows any typed
nec6x00a -sec -mas -flash 6500FAST.BIN
But to be honest, I didn't know if the cd drive was a secondary master or not. Regardless nothing was changed, not even after a reboot.