Yes, it is!
You have 3 things to do:
1. position "KeyBindingsDisabled=1"
2. postion "menu keys" delete values, so it looks like:
"
MenuKey= //Enter Menu, Default F3
MenuKeyUp= //Menu go Up, Default Num 8
MenuKeyDown= //Menu go Down, Default Num 2
MenuKeyCancel= //Menu Cancel, Default Backspace
MenuKeyScrollUp= //Menu Scroll, Default Num 6
MenuKeyScrollDown= //Menu Scroll, Default Num 4
MenuKeyEnter= //Menu Enter, Default Num 5
MenuKeyBack= //Menu Back, Default Num 0
HideMenuKey=
"
3. position Speed_Km=1 //Enable speedometer in KM
In my case it works only on Simple Native Trainer 1.0.8.0 - Cheat Menu version, but maybe older versions are suporrted too.
Works like a charm, and ther's no chances to activate, turn on trainer, menus and others.
So it's like the speedometer only mod.
P. S. It's been too long but i'm still playing GTA IV, so this post is for others who still did