Well, I took the 4 down to get the business done, slightly intrepid as usual.
To my surprise, it failed, LOL. However, this was only down to the number plate now that the law has become tighter.
So I get myself a new plate and fit it, lo and behold I get a pass, Woohoo!!!!
My 4, being indignant to such an easy test, I get to within 1/4 mile of home and i notice the temp gauge creeping up.........then it rockets to the red. I switch it off and coast to a halt, limp 50 yards to outside our house and leave it for a few hours to cool down.
Had some work to do, so went out to check levels and leaks, as you do, and when I go to top it up it is taking a while

all in the *BLEEP*ing rain. I can hear something above the rain and have a look underneath................the coolant is going straight through!!!!!!!!
In summary, my 4 will not accept an MOT pass without spitting out the drain plug in defiance and thus stripping the thread, only for me to now wonder on a permanent fix:
1. Bond a nut on to the rad
2. liquid metal a nut in to the existing hole
3. get a different rad
Any thoughts?