G1 Yellowed, Cancer Spotted, and Mismatched-Help!

[Virall]

Last week, i bought a lot of 3 Big Brother Ponies, which all looked pretty clean and spot free. They just came in today and they look rough. Apple Delight is yellowed (trying to whiten him in a mix of hydrogen proxide and water), Barnacle is covered in those "pink higlighter" marks and, what I'm assuming is, cancer spots, and Sweet Celebrations has a normal colored head but a dingy body.
I can post pictures if that helps, but is there any way to fix them back up? Im kinda OCD about ponies so the closer to orginial the better.

 

[Skybreeze]

Sun fading in a bath of Hydrogen Peroxide will help them all (no need to water down). It takes time but you will get great results. I find putting each pony in a glass jar in the sun works best, I get mine from the dollar store.

 

[Virall]

Sun fading in a bath of Hydrogen Peroxide will help them all (no need to water down). It takes time but you will get great results. I find putting each pony in a glass jar in the sun works best, I get mine from the dollar store.

I didnt realize it could work on the other two, since they're not white/yellow ponies.
I'm gonna have to try it out, thank you!

 

[Skybreeze]

I didnt realize it could work on the other two, since they're not white/yellow ponies.
I'm gonna have to try it out, thank you!

Just make sure you keep an eye on them because while it brightens dingy old ponies, it can also fade out the colour and paint of symbols and eyes/blush and hair of hair is still intact. You should also remove their tails before submerging them. (I don’t recommend doing this with ponies that have neon coloured hair or bright red hair.)