What kind of clunk? Driving on smooth pavement? turning? accelerating?
braking? is there a vibration? I suggest jacking it up under both the
control arm, and then under the frame. Checking both ways sometimes
will reveal play or loosness that may be overlooked.
I would jack under the control arm first and grab the top of the wheel
and shake in and out, then side to side, then the bottom rear of the
tire 5 or 7 Oclock depending on which side your on, this should show
any lower component play. Check stabilizer links and shocks {most common}
or any foreign objects possibly a cat? {two in 86, possum in 88) the second
cat clunked for a little while. My neighbors, Iloved that cat!

Good Luck and Be Careful!!