I unlocked my 1700+ and it was a pain, but fun also. I was so worried that I had destroyed my CPU when I had to scrape it a few times with a razor blade.
The first time was to remove excess super glue the second and the third and the fourth was to start again when I screwed up.
On the last attempt I figured out the best way to do it and it went like a charm.
I used the guide at tomshardware.com and instead of using the silver laquer they used I used a circuit pen from Radioshack.com.
I haven't done any high overclocking yet, because I am waiting on my PAL8045 to arrive, but I am running at 1575Mhz.
I upped the multiplyer to 11.5 and upped the fsb a little too.
Don't try it unless you are willing to risk killing your CPU. It may be rare, but can happen.
Mark