Coolant header tank
 

What pipe do you need to remove to empty the coolant on a classic as I want to remove the main header tank so that I can get it powder coated please thanks .

i think there's a drain tap on the bottom of the radiator on the drivers side

I usually take the lower rad hose off, the taps have a habit of snapping!

Remove the turbo to header pipe. Then unbolt header. Pull it up as high as possible. Then remove it's bottom hose catching the coolant that come out.
If you keep this hose tied up somewhere as high as possible you won't loose much more coolant only what was in the header.