Ball joints

[GTRS Fiero]

For an '88, I see front upper and lower ball joints.  It doesn't specify front or rear.  Are the ball joints only in the front?

[TopNotch]

There are no rear ball joints on an 88. Only bushings.

[GTRS Fiero]

So, if I replaced the trailing arms and bushings, I should be good in the rear?

[TopNotch]

Just the bushing, including the ones in the arms, if they're bad. Chances are, the trailing arm bushings will be OK. The other ones are smaller, and more likely to need replacing.
But if you're experiencing rear problems on an 88, it could be that your rear knuckle long bolt holes are worn. Rodney Dickman sells a fix for this.

[GTRS Fiero]

What other bushings in the rear are smaller and more likely to need replacing?

Somehow, at 60K miles, my trailing arm bushings were worn out.  I wasn't really experiencing any issues.  I have the girdle/long bolt kit in my RD cart.  I'm waiting on the steering rack bushings.

[TopNotch]

There are 6 bushings on each side of the 88 rear suspension. Two on the trailing arm, and two on each of the transverse arms between the cradle and the knuckle.
In the drawing in this thread, the trailing arm is part no. 18, and the other arms are parts no. 39 (solid), and 44 (adjustable).

[GTRS Fiero]

Ok.  I replaced all 3.  The TFS kit.