For anyone who is familiar with this product, you understand how well it cleans without being too aggressive or leaving a film or residue.
I wanted to share the method I find gives me great results and some pictures.
I use 1z Plastic Deep Cleaner.
I use a horse hair brush like this one: Natural Horse Hair Interior Upholstery Brush
The process itself is pretty straight forward. Remove any surface dust with a mf that has had cockpit premium misted on(just enough to generate some grab in the fibers). Use a long bristle brush to clean out any dust cracks or crevices. If you don't remove the surface dust, you may make a mix that is extra nasty. Working 1 section of a panel at a time, use the horse hair brush with enough 1z PDC to generate a foam while cleaning. Depending on how dirty the panel is, you may clean a lot of surface, or make 1 "pass" before needing to wash the brush out. Wipe up any residue after a "pass" with a mf towel. Use a compressor blow tip in conjunction with a mf towel to remove any build up in the cracks and crevices(which will be necessary if you're generating a foam). Be mindful not to just blast air in without the mf towel in the best spot. Otherwise you will have a mess.
Sometimes, if there is a thick build up in a crack, you may need to use a different longer bristle brush to agitate the build up before it releases.
When I say pass, I am using that term very loosely. A pass is not a single pass over the surface as much as it is a single mini-session working the brush and product before wiping up.
Between the soft bristles of the horse hair brush and the 1z PDC, I've been able to clean just about anything off of a vinyl surface. Because it is gentle, I use this same method of a dashboard and get great results every time. If you're using it on a larger surface like a dashboard, you should really work in small areas though. I find you get consistant results working smaller areas.
I like to top the cleaning up with a solid wipe down of 1z Cockpit Premium
This is not the absolute fastest way to get "good enough" results that some people are looking for. In other words, if you do this professionally and are not charging to spend a notable sum of time on the vinyl, this may not be the best option for you. But if you do charge accordingly, I believe this is one of the best methods to get really really good results. It is time consuming but oh so worth it.