Don't use adjustable rear camber/toe brackets. There have been a number of cases of these failing, and one popular type is very badly made indeed.
Far safer to measure, calculate how much you need to move it, file the hole, and weld on a thick washer to locate the shaft properly.
To calculate the amount to move the hole centre, find the overall length of the pivoting part of the arm plus thrust washers, i.e. the distance between the inside face of the outer bracket and the inner subframe web. A tape measure or steel rule is accurate enough. I don't have the figure to hand, but it will be the same for all Minis. The number you get in mm should be divided by 57.3, and again you will use that number, once established, on any Mini. Let6 us call it X.
Now supposing that you want the camber to go 2 degrees negative (I don't advocate as much, it is just an example of how to do the calculation)from its current value, and the toe 0.25 degree inwards, on one side, So the hole has to go 2 * X up, and 0.25 * X forwards. That will get you in the right place, consistently, if you can measure the hole position properly.
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