Trans mount part number ID please

[Fast67VelleN2O]

I have a near mint, early take off trans mount with a part number of 3928392 cast into the rubber. Any idea what the original application is for?
Thanks
Matt

[Mr70]

Originally used on Auto Trans:
*1968-72 Corvette w/o TH400
*1967-72 Chevelle w/6cyl.
*1968-69 Camaro w/o TH400,or 302 or 396cid.
*1970-72 Camaro w/6cyl.or 307 or 350cid.
*1968-72 Nova w/6cyl.