State of the Game

I was thinking of something similar to the arms on a Robobrain from the Fallout games - a rigid skeleton based on universal joints that utilizes cables and hydraulics to mimic the flexibility of a tentacle and covered with a metal flextube (similar to armored electrical conduit) with a grasping claw on the end.  It's relatively simple to create with technology of the era and would only require *some* reverse engineering of Martian technology to effectively control and power.  I imagine it would also be far larger than the average Martian mechanical tentacle due to it being an Earth version of Martian technology.

I also think that a 'Grappler' tank using this technology would also need armor that would be more resistant to Martian heat rays.  Brick, while being low-tech, is readily available and could be placed on a tank so as to reduce the effectiveness of the heat rays considerably.  But the heavy weight of the brick would need to be offset some way, perhaps with a diesel/kerosene engine with an early version of a compartmentalized, self-sealing fuel tank that is also based off ideas learned from studying the self-sealing hulls of Martian tripods that help maintain atmospheric seals that keep Earth air out of the pilot's compartment.  (Granted, I'm assuming that the Martians have this tech, but it stands to reason any intelligent race that knows how to travel through space would know how to deal with hull punctures quickly and efficiently).