Greetings, I believe the powerpoint I have uploaded to Google Docs and linked here is an invaluable resource. While directed at airline maintenance personel (where training on this subject is an annual requirement), it is an excellent visual aide showing good and bad wiring examples. While an amatuer built aircraft doesn't have to comply with every rule in the book, it doesn't cost very much (if anything) to follow the good advise in this powerpoint. See Slide 128 for beginning of discussion regarding wire insulation choices. There is no perfect choice for wire. Be sure to view the notes attached to each slide! https://docs.google.com/open?id=0Bz7qR_bMoJoQYzI5OGM1N2MtMjVmZC00YTI0LWFjOTUtOTZhNjAxMzg5YjZm This file is about 12 MB.