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In one of the videos it says the button location should be the bed length minus a mm. ie Ender 3 bed 350. However, in another video you show Auto homing the bed and then counting the distance from its home position until triggering the switch. Is this a difference in the MK2 and MK3 versions? I want to make sure I add the correct values. Also not sure what the ramifications of getting it wrong. Will the bed ram against the switch and not stop, if the value is too high, if to low never will reach the swtich etc.