By scrolling do you mean move? Scrolling is what you do with scroll bars, if you want the element (in this case an iframe) to be in a different spot, its move.
I only ask as scrolling could be very difficult, if not impossible (I have never had to do it so don't know, would have to look). Where as move, while tricky is a bit more doable.
I think the better question, is why you would want to do this?
I do not think JavaScript is the best thing to use.
Try using an <a> (anchor) element around the element where you want the top of the frame to start then reference it by using the name attribute like this:
Code:
<a name="whatever">START HERE<a>
then when you start the iframe call the URL like this:
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