S-Line bumper on to pre facelift

S-Line bumper on to pre facelift
8P 2004

Just looking into the this option, i have the split grill and looking into swaping the bumper for an s-line.

I know i will need a new bonnet and fog light surrounds but will i need new fog lights?

Is the bumper on the s-line the same through the years 05-08?
Did some have an extra piece on the bottom?

Will my under carriage be the same

Thanks in advance.