[Barrykgerdes]

The release version of Stellarium does not have comet Halley in it. This file will be placed in the \stellarium\data folder by default. It will not overwrite anything in the user section. However if there is a ssystem.ini file in the user area it will take precedence when Stellarium loads.

I have an older large ssystem.ini file that does include coords for p/halley. The orbital parameters place Halley at 8h 28 52.8 and 2 08 26 (J2000).
The orbital parameters from this thread place Halley at 8h 30 59.9 and 1 58 35.0 (J2000) when inserted into the ssystem.ini file.

I don't know which is the closest. If you have some later sightings that agree better then use them. You could also feed the coords from 3 or more sightings over the last 20 years and generate a new set of orbital parameters yourself that should improve the overall accuracy. Don't forget to compensate for light speed.

Barry

Here is a large ssystem.ini file to try