Answer to: How to solder a replacement LCD Connector?If you are in New Zealand, Jaycar has the same soldering iron (or very similar) as the one iFixit sells with the correct voltage and plug. They can also supply you with solder paste or solder, flux pens and desoldering tools as well all of which will help with the jobs you want to do. Hope this helps
Answer to: How does reflowing solder not damage the chip?Reflowing is generally a short term heating not much longer than a minute maximum in production settings, and reflowing is hotter to melt the solder. Overheating is a longer term proposition which causes damage to other components as well, that been said if heat applied during reflow is extended it will cause damage just as overheating will. Carefully application of heat during reflow should not damage chips, and if you follow to the time and temperature suggestions in the ps3 guide you will not damage the chips and successfully reflow the solder under the chips.
Answer to: External Western Digital broken harddriveI have seen these drives lose the partition on them, unfortunately when you create a new partition on them your data will be lost, I am not sure as to why the partition disappears but as soon as a new partition is put on them they seem to work. I also opened them with no ill effect in this regard, they seem to work fine after been opened, so check to see if the drive still has a partition on them if not new one should fix the problem (caveat been the drive will not have any data on it if this is the case) Hope this helps and Good luck Doug