Thanks for the input.
I've double checked my infinity setting, so I'm taking the rangefinder off the camera as per Jo Lommens instructions.
Since the rangefinder arm loses contact with the cam at 8ft regardless of lens, I'm going to adjust that.
Dan - I've found the instructions for adjusting the cam, and the rangefinder. Given that the instructions call for a 4ft focus with the standard lens, and mine is only capable of 8ft with the standard lens, it seemed like there was something wrong!