do you have to get all the scratches from the sandpaper out before you start to paint, or will the paint eventually cover them up? I ask this because I wasn't happy with what I had done, so I decided to start over. I think I used a too aggressive sandpaper and left scratches that I didn't notice (probably because I was in a hurry to get started again). Anyway, I got the consistency of the paint down now, but there are scratches that I can see through the first two coats. Do I need to take it back down and get all the scratches out? I'm guessing yes, but hoping no. Thanks