Paint treatment radical?

Hi, I bought a Vectra A V6. Since you can’t really throw money around as a student, my father has repainted the badly scratched and several times wall-tested original Opel Sport spoiler with the small SATA. The result is great for a garagehobby painting, but unfortunately some parts have got light orange skin. To get these parts nice smooth I planned: -Nasschiffiff 1000/2000/3000 -Sonax paint cleaner by hand -Sonax Nanoversiegung Elung, apply with a Bosch Profi eccentric grinder with adjustable speed and medium-hard foam attachments. Unfortunately, the grinder does not offer me forced rotation, since it is a professional device, I have not yet managed to make it stop. Soo, I would like to hear a few honest opinions (Zimperlichkeit is not desired, I want to learn something here and not be cuddled) about my project.