Will probably attempt the repair today. I have 2 chances to get this right (2 logic boards) but i'd like to get it right the first time around. Although we don't have the fine tip soldering irons, the tips are fine enough to contact each individual lead without any issues. Here's hoping for the best anyway... i'd love to have even one iBook that's been repaired properly. I may even go the full amount and scrape the varnish from the logic board for a greater surface contact point. Generally this ensures the repair will last and the information can be found here:

http://www.xlr8yourmac.com/tips/iBookG4_vreg_repair/ibookG4_vreg_repair.html

Funnily enough I have managed to resolder the Vreg chip before, but it cracked again shortly after... so part of the job will be an upgraded connection to the board and then of course epoxying it into place to prevent a flex and crack again. After all, a job worth doing is worth doing well- so I may as well go the extra half mile and make sure it's done extremely well.