sunfading discolouration AND pen marks?

[CarnationTwirl]

So I have a not so pristine Princess Pristina who is overall discolored from her electric chartreuse hair, as well as picking up a few stray pen(?) purple marks.
Do I sunfade the whole pony and the pen marks will go at the same time?  Or is there a different procedure for that?
I'm not worried about protecting her medallions in the fading process, as one was broken and both have been removed for the sake of trying to make copies.

Also, has anyone had any experience in using UV bulbs meant for reptiles for indoor sun fading?  Days are starting to get longer, but I'm still on the shady side of my building.

[Elisto]

I've sunfaded the bleeding from Surprise's hair before (similar color, or the same?), and yes, I would just sunfade the whole thing (though you might want to cover the hair/eyes). It might take a while I've also sunfaded dark colored ponies with pretty good success, but you still might want to frequently check to make sure the body isn't fading.

[CarnationTwirl]

Yeah, it's the same hair as Surprise.  It was faded, matted, and half chopped off so she's getting all new hair after I'm done fixing everything else.