Kers mapping for logitech g27

[Gudjion2]

Guys I can't assign kers to a steering wheel button on my G27, I'm using a cronusmax but gt sport won't let me assign anything to r3

 

[Lord Protector]

Because R3 isn’t on a G29...

 

[Greycap]

Because R3 isn’t on a G29...

Excuse me what? Right next to the MFD dial.