Check out this link; it is to a page in the multi-volume report of the US Army Engineers in the SW Pacific. If not in any large library near you, These volumes can be borrowed via interlibrary loan and the US Army Military History Research Center.(old name). More when I have time.
ps. I wrote my Ph.D thesis on the 978th Engineer Maintenance Company that served in the ETO. I THINK I may have some material related to these companies. I do know the first was the 56th Engineer Shop Company which in turn split with part of it (475th) ending up in Iceland. It provided the cadre for the 978th...which in turn provided cadre for the 1478th AND the 1487th Engr Maintenance Companies.
The Table of Organization and Equipment (TO&E 5-157) identified a hq, contact and two maintenance platoons. How the companies were used proves more complicated. Some were in the combat zones, some in communication zone etc. The 978th for example was attached to the XIXth Corps in the ETO, and the Corps engineer officer wanted it as close to the front lines as possible. Others in other organizations were kept back......
theron