Don't bother man!!
I stripped my skyline of everything except the dash and I only lost 40kgs (the weight of a small child)
Not at all worth it!! not even a bit of it!
And by the time you remove the Aircon pump, rad and pipe work, that's only maybe 10-15kg!
If it was a stripped out race car, you'd pull absolutly everything out and it would make a bit of a difference!
Dan