What bolt size req'd?

[Red '88T]

I'm looking to buy a fitting for my coolant supply line to my T04R DBB turbo. What is the required thread size and pitch needed to fit on the thermostat housing for the turbo coolant supply?

I think it's a M12x1.25 (or x1.5?) to -6an (using 6an coolant lines for turbo).

Can anyone confirm this?
Thanks!