Thanks, Greg.
OK, a bit of wisdom for everyone. Basically, wiring in the interior do not become brittle except in very rare circumstances (a convertible put outside in the weather with the top down for years is a good candidate). Brittle insulation can be found under the hood, where heat and exposure to the elements is much more common.
The main problem with interior wiring is that previous owners hacked, murdered, and brutalized the wiring. I've seen everything from wirenuts to Western Union splices. The other main concern is that various pins need to be re-crimped due to age; this is especially problematic in molded connectors which are almost impossible to repair except by replacement. The other less common issue typically seen is wire insulation that has melted due to excessive current flow. Examine all of the wires closely to see this, and also examine the wrapping tape to see where it has deformed/melted. Finally, fuse box clips and some connectors do get rusty, but standard methods of rust removal work well.
