Combining Kitti-output with Images

I am using a video and outputting the respective bounding boxes through the kitti-output-dir; but these are useless to me without associating it with the respective frame.

Is it possible to save the frame as well as find some way to uniquely connect the frame number with the kittit output directory files?

You can use dsexample plugin to save frame, source code here, sources/gst-plugins/gst-dsexample, meanwhile, you also can save kitti bbox output.

I am in that directory; do I need to make the files before using the plugin? Is there an example of it being used inside of an config file I can take a look at it?

currently no, you can refer to this thread for how to save frame to file