Cozwurth,
Yea, 2" off both ways can easily equal a miss, even on the fox. If the scope won't hold zero, then you are right to get rid of it.
The scope I purchased just for the home-made NV outfit is a Bushnell Banner 4x16, Dusk to Dawn, illuminated reticle with an adjustable objective. I think if you put this home-made night vision job together, it will be important to have the ability to adjust the parallax of your scope for the distance you will be shooting. I think that was the problem with my point-of-impact drifting previously. After I got the Bushnell and adjusted it for parallax at the 60 yard bait site, and then sighted in the NV to that distance, it was dead on target.
Sighting in at your bait site to hit dead center is the important thing so you won't have to worry about trajectory. Wherever you expect a coyote to appear, that's where to sight.
This evening I have attached the new DVR recorder to the NV outfit, and will now be able to record video of what the scope sees. I set the outfit up on the bannister of my front deck, and looked at a gallon milk jug that was approximately (guessing) 60-70 yards away. I videoed "through-the scope" from 4X all the way up to 10X on the Bushnell. Looks like somewhere around 6X will be ideal. I took my last coyote with it set to either 7 or 8 power as I recall, but lost some field of view at that distance (60 yards). I'll post a video once it uploads. It's slow loading for sure.
UPDATE: I just now got the video uploaded. It took a while due to my slow computer speed.
Anyway, keep in mind that the recorder doesn't show how well the LCD actually sees. This one looks a bit grainy, but the LCD doesn't see the grain. It's pretty clear.
I have noticed that the camera needs to be focused when changing various scope magnifications. I have found it better to zoom to a desired magnification, focus the camera lens to that, and quit. When zooming in and out, it becomes blurred. I'm thinking somewhere around 6X is going to be about right for shooting at the 60 yard site, though I could get by with much less. I just like to be able to see the crosshair well enough on a critter to make a shot. I could actually use a 4X or a 5X, and that would give a better field of view.
Here's the clip. Click on the photo to see the video. Hopefully I'll get better video later once I play around with the NV camera some, adjusting for sharpness etc.
This video may not look very impressive, but what the LCD sees is much better.