torque convertor drain

[1980sel]

Can anyone tell me how much fluid comes out of the torque convertor..and also what size hex is the drain plug...this is on a 1980 450 sel.

[oversize]

I think it's a 5mm hex male that's needed & it's been so long since I've done a change I can't remember the litres... Maybe 3L without converter & 3L more with?