Do you need to flush the coolant system when removing the upper radiator hoses? I want to just change the top 2 coolant hoses to Red Samco hoses just like the picture below.

 

you dont have to but top it back off before you go and play with it. And dont mind the bit of smoke from the rest burning off.

 

No, you don't have to flush the entire coolant, although highly advisable... Just drain as much coolant as you can before it spills all over the place when the upper hoses are removed. However, add new coolant when it's time to fill 'er up.