I used a wool ball on a stick the wool was about 1/2" round. Didn't take much and got lots left so if you need to do yours don't buy any I'll give you some.
Your engine the last time I saw it looked great what did you use to keep it that way?
The alum intake was clear coated when new 13 years ago. Getting dull & stained, won't clean off completely. I should have restored it last year on engine rebuild. But I was in hurry to get running.