Just purchased a used original roto grip cell. Has 3" pin. PAP is 5 1/8 over and 1/16 up. Have below average hand and have a high track. I am looking for suggestions on how to drill the ball. I need something for heavy oil, afraid to drill the ball too aggressive. Have heard over aggressive drills on this ball can lead to terrible roll out. Any ideas?

Thanks
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Get the 5-7 out! Geez