[Christ]

Since you can't swap in a manual, how about swapping in a newer OD transmission from an Escort? I don't know if that's within your zone of comfort.

Aeromodding is a given, obviously, but the question is how far are you willing to go? You can easily make some paddle mirrors, vent the rear of the hood to slightly alter the windshield/hood angle, which also allows better venting in case you wanted to try out a grille block or a belly pan.

Not sure what you're into visually, but smooth wheel covers or rear wheel skirts will help. Check that your rear bumper doesn't create a parachute for air under the car. If it does, you can either trim it out and make a diffuser, or you can just make a tray from the spare tire well to the bottom of the bumper to keep airflow from getting up into the pocket that the bumper creates.

Tire spats, combined with at least outer side skirts, possibly a second set of side skirts mounted inboard of the first set to isolate underbody flow and keep air from splitting around the back tires.

Lowering the car will get you closer to the result of a belly pan without actually having one, if you're not into that kind of modification. Check/adjust your brakes, make sure they're not dragging at all.

If you want more power from an exhaust mod, and you already know that the 2.3 was a Torque Monster (LOL), you'd want to figure out what size of pipe is necessary to aid low-RPM flow at high throttle angles. If I had to give an opinion here, I'd say no larger than 2 inch, and probably 1 3/4 to 1 7/8 if you're not going to be revving it up at all.

Any transmission from a 1.6, 1.9, 2.3, 3.0, or 3.2 Ford engine (yes, V6's as well) will fit, if you want to swap the Trans for something with longer/more gears. With the low-end grunt, and a properly running engine, longer gears to take advantage of torque will ultimately help out greatly.