Enjoyed reading your the page (linked above). Great research. A lot of time and effort went into it and it's very well done.
Quickly (more later because I'm in the middle of doing "Christmas stuff"), I am adding documents/links that may shed more light on the subject matter.
-
List of the various types of WWII engineer units and their functions.
-
Naples/Foggia Campaign
-
5th Army History - Also list which engineer units fought and where
-
http://www.6thcorpscombatengineers.com/docs/5th Army/5th Army History - part one - Activation to Fall of Naples.pdf
-
https://www.fold3.com/image/291745053
-
Photographic history of the Peninsular Base Section, United States Army : an illustrated history of Peninsular Base Section functions in Italy from 1 January to 1 May 1944
-
Records of Mediterranean - NARA
-
Engineers in the PBS
You may want to perform a search on the main site (search engine on Home Page), to see what else may be of interest to you
As far as the truck show in the photo you mentioned, it's my take that they were using whatever means available to them at the time. Not uncommon at all. So I don't find that, that unusual. Heck, they used whatever means necessary to get the job done. It's called being enterprising. :pdt34:
Not sure if you have seen this yet, nor how helpful it may be. Seems to be an overview. Peninsular Base Section, Italy - at Amazon
Hopefully I have not duplicated anything for you, but it may help others who are performing similar research. Of course, this is just the tip of the iceberg, but it's a start...
Merry Christmas,
Proud Daughter of Walter (Monday) Poniedzialek
540th Engineer Combat Regiment, 2833rd Bn, H&S Co, 4th Platoon
There's "No Bridge Too Far"