passthedutchie
Your off to a flying start with a cement slab floor spike your speaker into it and adjust the spikes so they don't move/rock even the tiniest bit in any plane
For the best imaging and depth perception, design it so there nothing between the speakers, and as far back as possible. (put your equipment rack off to the side not between the speakers).
The rest is fine tuning placement from back wall for the correct bass loading for your speaker/room
Cheers George