I am using Manganese and also Zinc phosphate. I was making my own solutions but couldn’t get it exactly right when I was testing it last winter. I decided to purchase the solution from Anthony Owens firstname.lastname@example.org and it is working great. You have to follow the directions exactly. When it says to coat the parts when you are done three time with WD-40 it is exactly right. I tried to get by with only doing it two times and it did not remove all the salts it creates. Here is a video I watched that helped me get started. https://www.youtube.com/watch?v=ExQguYKaJLg&t=123s
Phosphate coating requires oil to prevent rust and is what the factory used on many parts. Every year or so it is good to touch any phosphate parts with a drop of WD-4. it will sperad on its own. I have been told that after the parts are all done to coat them with Boeshield and it will not require any oil for years. I am doing a test now between WD-40 and Boeshield. I have two parts going to sit outside over the winter and see what happens. I will be in Minneapolis for work next month and will have access to salt spray test equipment and plan to do a little testing there also.
My trunk mat did have some glue in some areas but not much. I still plan to get some original material from SMS Auto Fabrics. From what I understand, there was three different style trunk mad fabric and all of them were somewhat close to each other in appearance. The sample SMS sent me was very close to mine but not exact. I will be using it anyway. My original is just a little to far gone for a high end restoration.