Man I have no idea. In my mind, those spacers would be needed if the collapsed measurement of the shock is too long. The extended length makes no difference unless you are worried about over extending your CVs; in which case you would want limit straps.
In either case, the collapsed or extended length should not be affected by moving the spring collar. So it should not make a difference what height setting you have.
That said, are you a gambling man? There are two possibilities in my mind:
1) The collapsed length is too long. So you need to install the bump spacers no matter which height setting you have.
2) The collapsed length is ok. So you do not need to install the spacer no matter which ride height you have.
The best way to decide is to cycle your suspension. This means talking off the coil and fully compressing the suspension and checking for interference.
@dirtydeeds do you have anything to contribute here???