Before you try those "extender" polishes, be aware that some of them are not just extra abrasive and more shine. SOme have hook retardants in them to reduced backend.
I'd suggest:
Since Resurrection finishes the ball around 800 grit, try sanding it to 1000, 1200 or 1500 grit and then adding your Snake Oil. This way you know exactly where you are, grit-wise.
With some of the "extender" polishes, it hard to remember exactly how much you applied and how hard you pressed for how long, if yo uneed to repeat the process.
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