I'm using acrylic paint. As shown in the pics, the red shows a lot of brush marks. The black is actually not too bad. But the flash light made the brush marks also pretty obvious too.
Although these are acrylic paint, I can try to add a little bit of thinner to it in the future. Maybe this will help too.
Update on the progress. I mentioned that I was not going to repaint the body. Well I lied. I stripped the paint and most of the primer off this morning. I'm using Tamiya Lacquer Spray Paint on the enamel white primer, maybe that's why the water-based paint remover doesn't take every bit of primer off by itself. But some slight brushing with a toothbrush and some sandpaper took care of the work. I re-primed the body around noon today. Arg...can't you believe I messed up this prime job again? so I had to strip that off AGAIN and wash and dry and everything. I broke a little bit of the body where the headlight goes on. The broken part should be covered by the light assemble, so I hope it is no big deal. Now it is 3pm, I just re-applied the prime the third time. I'm sure this one is fine cuz third time is a charm.
I will re-paint the body maybe Saturday. I needed to buy another bottle of metallic red spray paint. Hope it will go smoothly from here.
Question: Is it okay if I used acrylic paint to brush paint on the window? I need to paint around the rear window of the car. I read the FAQ, but it only talks about air-brushing the window.