1g's bont have upper control arms. Nor do they have upper ball joints.
With that being said, side to side wheel play is often from a tie rod, either inner or outer. Have someone wiggle the tire while you watch the outer that connects to the steering knuckle. If it moves, its bad. If it doesn't move, grab the shaft of the inner tie rod. If you feel it "clicking" , it is bad.
You will need an alignment if you replace one of these. It is nearly impossible to get the toe correct without an alignment.
In some rare cases, the lower ball joint may also give the feel of side to side play. More often then not, it will feel like up and down play. Might as well check it while you have the front end jacked up. With the tire about 3-4" off the ground, stick a bar under the tire, and pry up with one hand while your other hand is on the lower ball joint. If there is any play, replace it.
Hope this helps. Good luck with it.