BP-Business Home Sidebar not aligned

Hello,
Instead of 2 blog posts (in 2 columns) and a sidebar, I want 10 blog posts in one column) and a sidebar.
I changed .latest-block to width: 600px and .latest-block-end to width: 300px in layout.css.
It worked, but the sidebar gets aligned with the last post, instead of with the first one (with the 2nd post if it's showing 2 posts; with the 10th if it's showing 10 posts).
See print screen.
any help?
thanks & regards,
Edgard