What you will need:
1x Striking Scorpion Exarch body
1x Striking Scorpion Chainsword
1x Storm Guardian Chainsword
2x Shuriken pistols (preferably from a Dire Avengers kit)
1x 25mm round base
Greenstuff
Construction:
(I don't have the WIP anymore but I do have some photoshop magic)
first cut the ammo clips (!be careful here you will need the ammo clips later!) and grips off the pistols then file the area under the pistols body smooth.
Glue pistols to the outer forearms and use greenstuff to blend the pistols to the arms.
Glue ammo clips to the outer sides of the pistol (I put them slightly under the pistol but personal perference).
Glue Exarch body to base then glue arms to body.
Paint and base your new model
One I prepared earlier: