Yeah – Grey Knight terminator chest, regular marine back on top of Grey Knight terminator legs. The join between the two isn't the greatest, hence his slightly hunched-over stance. In hindsight, I think it may have been better to file down the 'bulge' on top of the legs (reduce by about 50%) and fill out the bottom of the torso with green stuff to give a flat join. Arms, backpack etc. all regular marine parts. The element I had originally planned but later changed was the shoulder pads – initially these were to be terminator-sized, to give a bit more bulk to the armour, but in the end I found that I preferred the size and look of the regular pads.
I'm glad I did it, and I'm broadly happy with how it came out, but I think that's it for my adventures into true-scale.