Well Brandon and I are
about being able to slide the sprocket that far. Sounds like a very loose chain.
On my Response, if you put set screws in the front sprockets, it looks ok at a glance, but using a straight edge it's off by a lot. I think the inner sprocket on the idler/counter shaft is not on the same centerline as the other inner sprockets. And if the frontier is like older argos, the lateral positioning of the idler shaft can vary an 1/8" depending on where the bearing set screw is tightened.
I would
take the set screw out and worry about why the chain's so loose
I like to use anti seize on the axle where the sprocket rides, as a lube.