Chevrolet aveo 2009 uk speaker wiring need help

[H4v0cagha]

Hi there
i have a chevrolet aveo 2009 uk model
i decided to change the original speakers on it and go with some after market jvc speakers.
i got all speakers installed but i am having trouble finding + & - of my speaker connection.
Any help would be great appreciated
Rear right seems to be light blue and dark blue
Rear left has brown wire and yellow wire
Front left has brown wire and blue wire
front right has brown wire and light grey or white wire