Best product to use for prep cleaning vinyl dash pad before painting?

[TKCR]

I did my OEM dash about 6-7 years ago. This is how I did mine:
Cleaned all the old dye with lacquer thinner. I was doing a color change, but it’s still best to take all the old dye off. I also made a makeshift paint tent in the garage with some big sheets of plastic. That way I didn’t risk getting any dust or anything on the dash while dyeing.
Next scrub the dash down to get any thinner residue off using SEM Soap.
Throughly dry and wipe it down with SEM Vinyl prep.
Then start using light coats of dye.
The last pic is 7yrs later. I just took this photo at the beginning of the year. I went from Burgundy to Charcoal. It looks really dark in the paint tent, but that was because of lighting. Since then, I have added LED light in the garage, so it’s a lot brighter now.
The dye is use is from USA1 Industries. They have all our correct colors for our trucks. SEM has discontinued most of our colors.