This conversion is a combination of Imperial Guard and Tau infantry to make a Tau Fire Warrior that is actually human.
The model is assembled by using Imperial Guard Cadian legs and removing the boots just above the top, these boots are then added to Tau Fire Warrior legs after the hooves have been cut off. A good place to cut is just below the knee pads, this gives you room to get the angle of the leg correct. The legs used from each set should be in a similar position to make the swap easier
The torso is a Cadian torso with the imperial symbol removed, as is the head, with the addition of green stuff (modeling putty) to make the visor and the tau helmet ariel. The torso also has the fabric at the neck removed and the head has some of the neck section trimmed down to make the head sit lower to the torso than normal.
The gun and arms use the basic tau arms but with the hand carefully trimmed off and replaced with a cadian one. This requires some very careful cutting. remove the tau hand from the wrist and level it off to the side of the gun. make sure the cut is level or there will be a gap once you add the new hand. The human hand needs to be cut from the gun and thinned down from the palm side until it fits against the tau gun. The left arm again is a tau arm with hand replaced. The shoulders of both were replaced with cadian ones.
A few human accessories were added such as the catachan knife, and pouch set and the human grenade. The scope for the rifle is a heavy weapons team targetter added instead of the small tau one.The hardest part of this conversion is getting the hands swapped for human ones (5 fingers!!) once thats done its fairly easy going. If you dont want to make the visor try using bare heads instead. The catachan jungle ones work well!!