Thanks for your reply
I have actually found what im looking for in the GUI Python files, it doesn't look too difficult.
However i can't find where the python files that defines the basic and advanced tabs.
I can see the section within the file mainWindow.py
(left, right, self.printPanel) = self.CreateDynamicConfigTab(self.nb, _('Basic'))
self._addSettingsToPanels('basic', left, right)
self.SizeLabelWidths(left, right)
(left, right, self.advancedPanel) = self.CreateDynamicConfigTab(self.nb, _('Advanced'))
self._addSettingsToPanels('advanced', left, right)
self.SizeLabelWidths(left, right)
Looking at the function "addSettingsToPanels" doesn't lead to anywhere either.