Michael, Can you confirm or deny the OEM finish on 69039? Perhaps do you have the original photo with higher resolution? Tim is correct in saying that the above shown pic is not perfectly clear.
PS: I have a home made, filtered air paint booth and remote air breathing equipment available to me in my own garage. Here is one of my bikes which I painted in Ferrari’s Rosso Fiorano using the Glasurit base coat/ clear coat. As I recall, the paint and chemicals alone were near $500. I would NEVER bother with that much work and expense on a road rash spoiler.
I just watched the video. The application of a textured undercoating was literally ONE more step than the normal painting process for any other single stage application. Everything else that was done in that video is exactly what would be done when re-painting any plastic bumper after damage. Our bumpers are fiberglass so don't need the adhesion promoters. That's cool that you paint as a hobby, I'm in the same boat. I have a 9x9 enclosed paint booth at home that I paint motorcycle parts, bumpers, and oddly valuable antique fans in. I'm no expert but from the sounds of it we're both on the same page in terms of our knowledge of painting. I don't use a remote air breathing system, always seemed like overkill to me. Anyway, long story short the complexity of actually painting a textured versus smooth finish is moot. It's not relevant to whether or not it was originally done in textured or smooth is all I'm trying to say.
And that car is wrong. You'll notice the rockers are also painted with a textured product. Goes nicely with the original dark tinting on the windows and the incorrect valve stems. .
Check out this car Vincenzo: https://rmsothebys.com/en/auctions/ny17/new-york---icons/lots/r025-1989-ferrari-testarossa/551917 It has nice shots of the trim.
Could be.... May be.... Can’t say for sure.... Nice car Jeff. Certified by Ferrari ‘should’ indicate that it ORIGINALLY came with a smooth finish. One would think. Could be....
Tim, the modern Glasurit paints can be quite poisonous without fresh air being fed to your face mask. Use great care! This is what I use... works fine: https://www.eastwood.com/hobbyair-i-system-full-face-mask.html
The catalyst in modern paint is the danger. It is cumulative to your body and does damage slowly. It contains cyanide.