knocking in front suspension

["lux" <molux@xxxxxxxxxxxxxxxx>]

I have a '91 e30 @ 54k miles.  I just had the sway bar links and the lower
control arm bushings replaced with stock replacements from BAV.  The car
still makes the occasional knock-knock when I drive over a series of small,
closely spaced bumps.  Before the replacements, the car would knock going
over any bumps or potholes.  Both tie rods were replaced about 8k miles ago.
I feel like the sound comes during an extension part of the suspension's
movement, although this is difficult to confirm in actual driving.  The
sound is definitely on the driver's side.  Any help would be appreciated.

Incidentally, the mechanic charged me 4 hours of labor to replace the
Control arm bushings, and 1 hour to change the sway bar links.  He said that
the old CA bushings were corroded in place and required a lot of effort.
Comments?

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