Purging lines before changes

Hi I've got a 912UL on a special light sport aircraft and and will be doing 5 year rubber replacement and 200 hour service on the carbs very soon.   Letting a rotax certified mechanic do the carbs, fuel pump, oil lines, and rotax water lines (anything that's a rotax line)  but my local A&P mechanic will do the radiator lines and fuel lines (I've got teflon lines to the pump so those don't need to be replaced it just the fuel tube from carbs and fuel tank and electric fuel pump).  I read the oil lines need to be purged before changing which is why I'm opting for the certified mechanic to do this, is there anything specific for the fuel or radiator lines I need to know other than drain the fluid first?