basically you get the car you want and press ctrl+w and in the customization menu you set the coilover option to empty on the front and back wheels and ta-da! Please not this does make the handling worse.
Good tip for those who want it, but please don't attach images onto your post, just insert them using the tool under attaching files!
The Grand Marshal looks fantastic without its springs on steel wheels. Its a bit of fun getting stuck on every second bump too, thanks for the tip.