I cheated a little bit as I only polished with paper up to 800 grit then used a buffing wheel to finish it. My suggestion would be to
try some spots all the way to 2000, then a spot at 1500, and a spot at 1200 etc, and see which one you can live with. The clamps
have about 4 hours just in them and the whole cat-back probably has 30 hours invested.