I don't know this "for certain" but before I changed my guide rod support "ball joint" on the passenger side I would get an unusual clunk on occasion from the passenger floorboard area.......as these are mounted directly in front of the passenger and driver footwell....and depending on wheel balance, and/or shock absorber wear.....I would think that you might get a noise like you describe.

I might be way off base here, but from the noise that my car made on the other side (sits by exhaust header) it sounds plausible to me.

Also of note: The rear sway bar links can also make an odd noise....found that accidentally while tightening the car up in cornering.

SB

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Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG