You can use Clothes Converter or Crossdresser to fit Aiko 4 clothes to/from Aiko 3.

http://www.daz3d.com/i/3d-models/0/clothes-converter-4?item=9309&cat=&_m=d

http://www.evilinnocence.com/crossdresser

I have both pograms and use them on simple clothing meshes. They give you a fair result but can distort intricate clothes mesh (buckles, strings, etc). Also somethimes they can stuff up the fall off zones causing clothes to break apart when posing.

Important note: these conversion programs are CPU intensive.