So ... I had to flip the model 180 degrees around Y axis and in Lua raise it 27 units in Y axis. I tried raising it in Fragmotion and the hands and sticks parted company, 3d modelling apps make no sense to me at all.
Part of the problem is that when you reposition the player the origin point is not the players eye position but the hud elements are centred on the eye, I presume the player x,y,z in game is the position on the ground directly under the centre of the torso?
Also the animation is all pants, assuming the sticks control the direction of the mech, like steering a tank, and left button for guns, right for rockets then you'll need the following animation sequences at least:
1) Straight ahead, the default anim, both sticks level with hands on.
2) Left turn, left stick towards player, right stick away from player. (equates to A button press)
3) Right turn, left stick away from player, right stick towards player. (equates to D button press)
4) Guns - left button pressed down. (will equate to left mouse hold)
5) Guns - left button release. (will equate to left mouse release)
6) Rockets - right button press and release in one animation.
If you want to be able to rotate the 'turret' then possibly you'll need:
7) rotate to left, both sticks lean left.
8) rotate right, both sticks lean right.
(edited to add: and animations back to the default from each one of course)
Then, if you really want to go all in, all of the movements in addition to button presses!
You will probably also want an initial animation of the player grasping the controls, and one releasing them in preparation to exiting the mech.
I can probably limit the look around so that the player cannot look down to their non existent parts but it might help realism if the arms could be extended to the shoulders. Oh and maybe a few tattoos and shirt sleeves.
Been there, done that, got all the T-Shirts!