Installing loudspeakers

How can i install tow loudspeakers of 6 ohm impedence (250 watts each) with two loudspeakers of 8 ohm impedence(500 watts each) and connect them with the same amplifier having the following features(FA2401(Name)-output power 8ohm,rms,stereo,===>2X750 watts

4ohm,rms,stereo,===>2X1150 watts

Bridged mono 8ohm,===>2300 watts

Paralel 2 ohm,===>2300 watts.By the way The amplifier has two channels with 2 output speakons and two binding post outputs.Thanks in advance.