Coating structure and sealing of the rain channel

Hello, I am about to finally miss my beetle in the self-built paint booth its final color. However, the longer I read in forums, the more uncertain which products should be used, I would be happy if someone looked at my planned paint structure. I stay in the “MIPA ecosystem”, nevertheless some components do not tolerate and from the data sheets I unfortunately also become not always smarter. r partially sanded down with the eccentric on the sheet, with the blank spots of a maximum size of 15 cm^2. Warm air ducts and fenders are completely flat. The rest of the old paint was sanded with P180. Now to my lacquer structure: 1. Large free surfaces are thinly fogged with Mipa EP-Primer-Surfacer. 1.1 Plastic part is sprayed with Mipa 1K plastic primer. 2. All the spots that have been pressed and the small blank spots are sprayed with Mipa 2K-HS-Grundfiller F 54. ht 2.2 The whole car body is sprayed with Mipa 2K-HS-Grundfiller F 54 2.3 Control black is applied and the car body is sanded 3. MIPA P99 Multi Star is applied to the still coloured areas 3.1 The spatula is sanded and possibly another layer is applied 4. The whole car body is sprayed with Mipa 2K-HS-Grundfiller F 54 4.1 And once again finally sanded (P400) 5. The one-layer Mipa OC 2K-PUR-Autolack HS quality is sprayed in two layers 6. Possible post-processing In addition, I removed rust from the “rain channel”, which created a groove there. Can I simply paint it normally, or should I seal it with spout mass or seam sealing MIPA PU400? Is this how it works? I would be very happy to receive feedback ;D When I finish (sometimes) I share my experiences with the self-made paint booth very gladly with you.