As far as I can tell, that particular hullmod is scripted internally in the games api, so you can't copy and edit the hullmod file like some others without creating your own script for it and compiling it into a jar, which is quite a bit of research and effort.
Well worth it if you want to get into modding starsector though.
What that file does is give a description and set a few attributes like op cost. I was going to do the same thing to reduce the cost of small mounts on capitals, but it can't even be used for that. (at least i couldn't get it to work)
Can't remember off the top of my head, but I don't even think the api supports a reference to fighter wings op cost yet, and so you cannot do things like effect their cost per ship. You also can't make specific wings -like only a hi tech bomber for instant- modified in any way either or restrict them by hull.
I can tell you that some of this support has been requested though.