Driver seat not level

Hey guys,

I've noticed it for a while now, but my driver seat is off kilter to the right. Any advice on how to fix would be great. Thanks

 

For me it would be more visits to the Gym and a subscription to nutrisystem. May not need a lift to get bigger tires on too.

 

as is in the cushion? or the way its sitting on the rails?

 

I think it is how it sits on the rail... I am the third owner of the truck, perhaps an old owner did some dmg to it