I wouldnt worry about it as much if i was sticking with green coolant. However, I am doing a complete coolant flush and would like to know which items are necessary to replace. I will be replacing the thermostat, but I am on the fence about the hoses and the degas bottle. My hoses are pretty new and in great shape. I notice that alot of people will replace thermostat, hoses, and degas bottle. After a flush, are the insides of the hoses and degas bottle still somewhat contaminated from the green coolant, making it necesarry to replace when switching to ELC?