Hello, got a stock HT-10 out of an S4 T2. I was grinding and sanding the rust off the exhaust turbine housing exterior in preparation for some black VHT Flameproof, but I noticed this little crack. I've got a couple pictures of it attached below.

The camera and the lighting is really fudging how it looks in person. It's incredibly tiny and shallow (the lighting is exaggerating it a lot). One of the pictures has my finger and a dremel bit for comparison. I've tried just sanding a bit more off to see if I could flatten it out, but after about half a millimeter, I decided to stop.

Should I be worried? I'm not sure how much I can safely shave off the exterior of these housings, so I don't want to overdo it just to get the crack out. On the other hand, I've heard that tiny cracks like these can quickly turn into a huge mess down the road. My car is almost completely stock (Literally no power adders so far) and it ran and pulled well before I took it apart. When I save up enough, I'll probably have this turbo pulled apart or replaced along with the precat and exhaust system. Can I use this turbo as is until then without fear of the motor nuking?

Hope I'm not making a mountain of a molehill here, haha.