My second to last major project was Astra Militarum and I have a lot of infantry special weapons left over (as evidenced by the grenade launchers). Each flamer tank is good for two terminators. A modelling or jeweler's saw to get a clean cut in half, remove the little curving bit which would sit on the Guardsman's shoulder, clean mold lines, then slightly file down the end that will be facing the power fist side.

You'll notice there's a triangular side. This is perfect for fitting into the back of the upscaled terminator's gap.

I made the hoses with a bit of bendy wire and greenstuff. I previously noted in my WIP topic that this project was the first where I saw how pre-made templates would save me a lot of time. One I got was the Green Stuff World rolling template. I roughly wrapped the wire in greenstuff and used the roller to neaten it up and add the ridges.

The tips I left bare to fit into the holes I had previously drilled into the flamer tank and the flamer mounting. I left the greenstuff to dry for a few hours to avoid getting finger prints on it when I had to bend it into position.