For 1.15.4 I made simply bigger Farps (the 3D model), so that the tailrotor collision couldn't happen.
Don't know on which of my HDD's the whole EECH modding is. Since the move I have no more plan where all my software is.
But it's not very complex. I needed an hour for it and had no experience in 3D before this. It was the first thing I made, cause I wanted to use 1.15.4 but there was this #%&*$# tailrotor collision bug.