The Puck Mod is not a true mechanical mod. To be a true mechanical, there can be no wires and the Puck uses a wired 510 connector and an electrical switch.
The main problem with making a true mechanical is that, in my opinion, you need to have some skill. You need a metal body to act as your ground, a switch that contacts the negative side of the your battery and the body only when pressed, and direct contact between the positive side of your battery and the positive post of your 510 connector.
I don't have a touchwood, but looking at the pictures, it appears that the battery door makes contact with the negative side of the battery. Then between the screw in the bottom, the switch, and the top plate, contact is made with the negative side of the 510 connector.
However, if you don't care that it is a true mechanical and just want an unregulated mod, that would be incredibly easy to build and you don't need as much skill. All you really need to be able to do is solder a few wires together.