Seeking information on 302nd Motor Transport Corps, Repair Group B (World War I)

Looking for reliable information about the Group "B" Repair Unit 302 Motor Transport Corps (US Army) during World War I (where a Great-Grandfather served), particularly where the unit was stationed during the war.  A long-standing Wikipedia entry without sourcing suggests the 302 was based at the Motor Reconstruction Park in Verneuil (Nièvre), France, but this has been extremely difficult to verify.

The unit may originally have been called Provisional Company No. 2, Mechanical Repair Shop, Quartermaster 302. Unit also abbreviated Group "B", R.U., M.T.C.

Thanks!