I eventually got the game work properly at widescreen

I used the widescreen method for FIFA 2005, starting at step 4:
http://www.wsgf.org/dr/fifa-football-2005/en

For the resolution I used Pdub's method:
viewtopic.php?f=111&t=52266

Here are the results:






Only issue I encountered is that backboards, coach and the players vanish from the camera when they cross a certain view area (probably needs a Hex edit to get fixed).

Nice! Good to find a new hack or mod, even all these years later.

I do not understand hex editing at all hahaha. Good to know about this, though. The game not taking up the entire screen has been very problematic.

This seems to be an easier fix for live 03 and 04.
1. Open your C drive.
2. Locate your Documents folder and open.
3. In the Documents folder, look for NBA LIVE 2004 and open it.
4. Then look for the cscripts folder and open.
5. right click on hwconfig and open with notepad.
6. You will see this...
r_hardwaresettings.nVideoMode 1
r_hardwaresettings.nScreenWidth 1920
r_hardwaresettings.nScreenHeight 1080
r_hardwaresettings.nScreenBPP 32
r_hardwaresettings.bGammaSupport 1
r_hardwaresettings.fGammaValue 0.5000
r_hardwaresettings.nTextureFilterType 2
r_hardwaresettings.bVSync 0
r_hardwaresettings.bTripleBuffer 0

CHANGE ONLY THE SCREEN WIDTH TO 1920 OR 3840(IF YOUR TV AND VIDEO CARD CAN HANDLE)
AND SCREEN HEIGHT TO 1080(2K) OR 2160(4K)

7. upper left hand corner click file and save from the drop down menu.
8. close file, load game and play.

NOTE: Title screens and all other screens will stay the same. Once you start the actual game, it will be full screen.
I tested this on 1920x1080(2K), but not yet on 3840x2160(4K)

Hopefully this works for you and helps!

Thanks. However there is an issue with widescreen, as it is not originally supported by game, you also need to change aspect ratio display. Otherwise players are stretched.

Another fun fact is the aspect ratio is same all the time. for 1280x1024, the aspect ratio of display does not turn to 5:4, it stays 4:3, you can compare that with screenshots.

This guide remains incredibly useful, as I get back to playing Live 2004. Many thanks, Murat!