invis in anim with Hex:
It is the difference between:
....sponson_hull_r.......................?
And:
....sponson_hull_r........................
By the looks of it.
So in HEX....
So the visible. Has: 803f
and the invisible has: 0000
So in the hex window of the anim when loaded edit the values manually for 80 3f replacing them with 00 00
An alternate way to think of it is to look between the next object and the object you want to change the visibility on. :)
You should be counting backwards 4 hex positions and there should be an 80 3F or 00 00, and this is the point you want to exchange there designation for.
As a caveat in the ANIM you must remember it is the second listing of the object you want to change the vis of, not the first listing from my experience.