Example of an update on a drive with unsupported firmware
Downloading the files
I had a Hitatchi TravelStar HTS548060M9AT00, which is listed as HTS5480xxM9AT00 on the IBM pages, so I downloaded the Floppy disk FWHD3413.exe. Then I burned the iso and I executed FWHD3413.exe to get a bootable floppy disk. Upon booting from the CD, it showed me that I had Firmware revision MGBOA53A and that there was no new firmware.
Preparing the files
Next, I took the floppy with the idea I could update the files on it to get the newest firmware, so I copied over FW.exe and FW.PRO from the CD. Now I only needed my firmware update tool and the according Firmware. So I opened FW.PRO and I searched for the according section which looked like this: