Best advise I can give is Do a test spot and start with the least aggressive grit you can. As with each step you must remove the prior sand scratches. Do a small spot and Look See, to see where to start. Only then will you know if you need finer or more aggressive grit. And make sure each step removes, the prior grits work.
Don't start with #80 of you can get by with something finer.
I have had to grind and sand road rash and casting flash, it is no fun starting that rough.
Also don't start to fine as well try a test spot with 180-220 and see what you need
I have over 45 years of experience polishing at a professional level.
I would not go finer than what black emery can remove. ( do not kill yourself going to fine)
Move to a new buff and gray emery then white rouge.
Finish up with Fine Speedy All Metal or Red Wenol to clean and or hand polish. Use one of these after to clean and maintain.
Remember use a dedicated buff for each step it's contaminated from the rougher steps product used prior.
This is important, only way I would cheat is if the black emery and gray one is shared but must be fully cleaned.
If you do cheat use a freash buff for white rouge this is the color (Depth)