Forget all about 1 metre on axis.  To get  the best signal to noise ratio the mike needs to be close to the speaker.  To reduce the accuracy with which the test speaker has to be placed on its bench mark and to get  a reasonable integration of the drivers in a system the mike needs to be placed away from the test unit.  By cut and try you find the best solution for your environment.

Try to arrange things so that systems fire horizontally and away from the operator.  This arrangement minimises the effect  of the operator on the measurement.

Test the speaker in its "normal" position, ie with its bottom at the bottom, otherwise you will have scratched cabinets!

Forget having the speaker on its back with the mike above.  Guaranteed bad news - connecting up is a faff, and the operator's head becomes the biggest variable in the measurement process.