cj10,
Firewall: If memory serves, I think I ran a tachometer wire (for a remote starter) through a small, unused, black rubbery/plasticky grommet just above and to the right of the gas pedal.
(That point of view is from the interior of the car. Look at the gas pedal, look up toward the headliner, and look to the right toward the passenger side of the car. At least that's how I think I remember it.)
Steering column:
Sorry I don't have any pictures.
First, manipulate the telescoping steering column so it's pulled all the way out, as close to the driver's chest as possible.
Remove one screw on the underside of the steering column cover; you can see it by just laying down, looking upward. There are three holes; two are just "dead end" plastic holes with nothing in them, while the third has a silver screw in it.
Next, get yourself some kind of tool you can use for prying that won't scratch stuff. I use a small plastic door-panel removal tool. You can just use a regular flat-head screwdriver if you're patient and careful, or consider wrapping the head of the screwdriver in tape.
TIP: Cold plastic panels are brittle. I'd imagine it's not very cold where you are, but regardless, make sure the interior is at least fairly warm. If it's chilly outside, run the car with the heater on for a little while.
So anyway, start the engine so you have the power steering working.
Sitting in the driver's seat, turn the steering wheel a little to one side, and the part of the column that was concealed while the steering wheel was straight....take a close look there. You can actually see a little notch made to insert a pry tool. Just pry up there. Now turn the steering wheel the other way, and pry that side up too.
So now you've got the top half the the column shroud pried up and loose. (It'll still be flapping back and forth on a piece of vinyl; just leave it like that.) So now remove the two screws you exposed by the prying, and pull the bottom half of the column shroud down and away.
TIP: It's so hard to explain this in text, but as you're pulling the bottom half down, keep your eyes around the ignition keyhole. If you'll look closely, you'll see that the column cover has a sort of slot in it, and that lines up with a tab that's part of the steering column. (There's another on the left side too.) When putting the car back together, make sure you line these slots up correctly.
ALTERNATIVE TO STEERING COLUMN: I think there's another place you can go, especially since you're doing alarm only and not a remote starter.
On the left of the driver's dash, if my memory is correct, there's a gray "woodgrain" panel with a green ECO button on it, and below that, two regular black buttons.
You can pull the woodgrain/eco panel off with your bare hands, and unplug the switch.
Then, the panel below, with the two black buttons, will pull off with your hands as well.
With those panels off, you have a full view of the underdash fuse box. At the top, is a large plug without about five very thick wires. If you test ALL of them, I'm pretty confident you'll find constant and ignition right there.