Removing gelcoat is a real bear, but it shouldn’t take that long! We use an electric DA, like RIDGID with 60 grit pad to remove 50% Down to where the underlying cloth starts to show. The remaining gelcoat is much softer. Works best on flat surfaces like the a stab.
Be very careful on concave surfaces like the underside of the elevator. If memory serves me, it should take something like 24 hours to completely strip a 15 meter bird.
Hope this helps,
JJ