I know very little to nothing about Track balls, but with pearlized balls from Ebonite, Storm, Brunswick, and Lane 1 (which I no longer use) I have had my best success by sanding them with a scotch brite pad to 400-600 grit....then polish with 500 Grit Ultimate Quick Cut Polish, followed by Columbia 2000 Grit Polish burned in hard. If I want a bit more shine, which I seldom need, I'll use Storm Xtra Shine applied very-very light. (about 1/4 teaspoon of polish on each half of the ball. I then spray the ball with water and really burn the water hard too. That works for me. Others have their own formulas.
For yourself, I would try scotch brite it to 400-600 and then use your Storm 1500 Grit Polish, which I assume is Storm Step 2 Polish. Then if you want it shiner, use one of your higher grit polish's. I've used the Storm Step 2 in the past with satisfactory results. Just don't get the polish on so heavy that you plug the pores.
If your ball is in really bad condition, you might consider taking it to a pro shop and have them put it in their Haus Machine. Then you can polish however you want.
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