I know this isn't JJ2, but I think this is about the only place I'll actually get useful advice.

In JJ1, I can't get more than 98% of the items in Tubeletric 2, 84 and 44% in Jungrock and about 50% in Sluggion. I've played the levels over and over, but I can't find the rest of the stuff, and I'm too much of a perfectionist to give up.