So, who can tell me how to make heat come out of the passenger side? I don't care personally, but apparently I should
drain your cooling system off- assume position again, and put a 15mm t piece in place of your heater passenger/driver distribution valve. should take just about long enough for you to pass out, and not be able to walk properly for an hour when you get out of the car....

https://www.two-sixties.co.uk/mgoc26...ead.php?t=5936