You have acquired some SWWEEEEEET speakers! I have spent many hours recording and mixing on these.
Start with your speakers pointing down the long axis of your room positioned at least a metre from the wall so that the two speakers and your head forms an equilateral triangle, and toe them in so the tweeters are pointing towards you.
To really get the best out of these speakers, you need to read up on room acoustics and figure out a plan to acoustically treat your room. The main problem will be first reflections, which bounce off the walls and then arrive at your ears - use a mirror on the wall and ceiling to see where these places are, then block off the sound path with absorptive acoustic panels (not too close to the wall), which you can make out of medium density Rock Wool slabs. As this is a porous-type absorber, they need to be very thick, or placed away from the walls to absorb down to as low a frequency as possible.
The next problem, which is harder to sort out, is 'room modes' - resonance frequencies that are most problematic at low frequencies. They have wavelengths which correspond to your room dimensions. E.g. your room is 4.3 metres wide; this will give you resonances at (340/8.6) Hz = 39Hz, (340/4.3) Hz = 78Hz, 117Hz etc. You need some serious carpentry skills and knowledge of resonaces to build some 'bass traps' that will absorb sound at your problem resonance frequencies to level out the bass response of your room, but with these speakers, it would definitely be a fun and worthwhile project.