This is a big restoration project and will take a lot of time and patience to restore.
Let’s start with the easy stuff.
1) You will need to open her up for this restoration and remove her tail.
2) Remove the washer from the tail. This is when I wash the tail as I normally would with shampoo & conditioner and that’s typically enough to get the rust off a tail that’s not too far gone. Your rusting doesn’t look too bad. Once the tail is dry, remove the metal clamp and replace with a zip ties and pull back through body once rest of restoration is complete. (I can take photos/video if you need help).
3) As very common in a lot of ponies at common “contact” points you have a lot of pin dot or inground dirt in her vinyl. These are those tiny black head type spots along the hooves and legs, looks like possibly on the neck as well but hard to tell with photos. It’s an easy fix with an Oxiclean bath in hot water.
Be careful not to submerge the tinsel in the Oxi bath as it will strip.
4) The pink is actually ink transfer from her ribbons that are (or were) in her mane. It’s very common for this pony. Looks like there’s also faint blue as well from her blue ribbons. Also the brownish ones look to be rust transfer. This all may come off with the Oxi bath. If it doesn’t you will need to sunfade.
5) The larger brown dots are the beginnings of pony cancer. After a good scrub in the Oxi bath this will help kill the mould spores that cause this. Then you will have to sun fade these spots to “remove” the markings from her.
6) That large blue mark looks like at some point she laid next to a fabric or possibly an uncapped marker and got ink in her vinyl. This is what’s going to take the longest to sunfade. Blue on a white pony isn’t easy to get out and it will take months of religious keeping in the sun to remove it. Now, to safely and effectively sunfade this girl you will need to cover her symbols, blushing, eye paint and her mane. I personally like to use masking or white painters tape but I know a lot of people use white tempura paint as well. (I don’t advise using a coloured tape as it may bleed into the pony too.) Then for her I would suggest using 40 volume hydrogen peroxide cream (hair developer). (Note: Do
not use anything with Benzoyl in it, it ruins the pony and seeps into anything else the pony comes into contact with as it continues to develop.) In a well ventilated space paint the hydrogen peroxide cream on to the troubled spots and place pony into a plastic bag and set her on a windowsill. You will need to keep reapplying fresh cream on the pony and because she’s white keep an eye on her as she can burn easily too.
Here’s the spots that I could see from your pictures of where each “problem area” is.
View attachment 39823View attachment 39824View attachment 39825
A fantastic resource for any restoration work is the
MLP Preservation Project. They go into further details of what each issue is there too.