Question about source code reading by Google

I have a heavy header, plus vbulletin's navbar coding, then a strip of ads coding before the content even begins on all pages.

If I wrap the header and navbar in a div style= position:absolute, top:Xpx situation, and then move that to the bottom of all my vbulletin pages calling header/navbar, like right before footer, and add a "margin-top:Xpx" to push the forum content down below it, that pushes all the real content closer to the start of the source code and looks generally the same.

Question is, does this matter to engines like google, etc? Will it make a difference in the value it places on pages?

ideally, your most important content is placed right after the opening body tag.
real-life, this isn't always possible.

I'd recommend avoiding absolute positioning at ALL costs. any layout that depends on it is a nightmare waiting to happen. absolute positioning is meant for flyouts, popups, and so forth... not page elements.

Agreed, understood re the absolute. I will test thoroughly with spacing if it goes that way. Just wanted to make sure it was worth trying in the first place.

A table and image based fluid header and banner, 2 strips of vbulletin based drop downs and the dropdown bits, login and breadcrumb coding, a strip of ads, all that is up top due to the way vbulletin, and most, template driven sites are laid out.

Looking to try something different to alleviate that. Thanks for your input.