i took the photo shop approach( layers )
in ableton live
the 3 samples were time stretched to 7 min and then merged to form a noise bed ,then elements from each sample were cut up and placed on the time line with fx delay , reverb, phaser,compressor
i did this several times exporting 7min wav files of the takes i liked
then i merged them all in audacity
resulting in the final stereo wave file