The starting point for this conversion is the Steel Legion Sergeant that is not waving an Ork head. That is this one here to the left. The laspistol arm is detachable. The chain sword arm needs to be sawn off at the shoulder and the blanket roll on the back needs to be cut off and the residue sanded away. Removing the blanket roll is probably the hardest work. Next the flamer/heavy flamer is probably best created from the plastic Cadian set. Glue the flamer fuel tanks on his back. This is why the blanket roll needs removing. Then cut the Cadian arm off at the wrist leaving the hand holding on to the flamer. Now for the arms. The easiest right arm is the plastic sword holding arm from the empire militia box set, the arm with a dagger strapped to it. The left arm comes as several bits. The Cadian hand that holds the grenade launcher or flamer works for this, plus the left shoulder of the empire militia bowman. After that depending on the post the 2 bits of left arm may need an extension to reach out far enough to hold the flamer. The easiest way to do this is drill holes on the ends of both arm bits for a bit of paper clip to hold the ends far enough apart. Once the glue has dried and the arm with linking paperclip bit bent to the needed shape, fill in the gap with green stuff. And that's it. The flamers shown here are heavy flamer conversions but the process for a flamer conversion would be identical.