I want to install a [component]. How do I get the [connections] through the firewall?

There are several methods. A good starting point for 1Gs is this post by Sean Costall (look for the section beginning "WHERE TO CROSS THE !#@$%@#$^@$#% FIREWALL ON 1G TALONS"). For the more ambitious, Brian Hood has pointer out that this location can also be accessed by removing the driver's side fenderwell (after taking the wheel off, of course).

2Gers should read this one by Brent Cook. There have been comments that 2G NTs may find the steering column boot the easiest to work with, since the other opening mentioned on turbo cars doesn't seem to be present on NTs.