67 charger sanding issues

[Scooter67]

Does any one have a suggestion for sanding the areas on the 67 charger that are located above the rear tires, just below the rear windows?
I've been sanding by hand with a cylindrical block sander but with slow results. I'm not a body man so if theres a power sander used for this application please scream it!

[b5blue]

https://www.harborfreight.com/power-tools/polishers-buffers/corded-7-in-10-amp-variable-speed-polishersander-64807.html 

[Scooter67]