Gorilla25, your on the right track, but only use the recommended amount of oil, no more no less, the weight you can play around with.
here is a link to the same thing your looking at doing, as we do it on 30 year old bikes, just to give you more ideas, and shows you it's being done even on older bikes
http://members.dslextreme.com/users/...rk_Springs.pdf
here is a link on fork seal replacement, I know it's not a Ninja, but the principal is still the same...
http://members.dslextreme.com/users/...nt_GS850GT.pdf
hope some of this info helps you out