One of those bore sight lasers would be nice. Use it to get the bore inline with the target and above and centered over the chronograph. Keep the chrono 10+ feet away from the muzzle. And you might try taping a couple cheap white headlamps to the diffusers and put them on low.
Now I haven't tried the headlamps myself, but it was on my "to-do" list before I blew my chronograph to bits. Chrony Information