can I put v10.7 on a MacBookPro3, purchased 9-2006 - currently have 10.6.8?
I don't think so. I think 2006 notebook Macs still use Core Duo processors. Lion requires Core 2 Duo. Check your computer. Go to >About This Mac. See what processor it's using.
OS X Mountain Lion System Requirements
MacBook Pro (Mid/Late 2007 or newer)
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