It looks like the damage at blogkindle.com was caused by prying off the glued components, rather than opening the case. The pads near the display connector that he labelled "Serial???" does look like the most promising point to connect. You could connect an oscilloscope to the pins one at a time during bootup to find the Tx line (especially if it was a "spare" kindle).
Last edited by geekmaster; 11-23-2011 at 10:56 PM.