Sorry I have not had time to dig through things to be able to give a more definitive response until now.
 
 
I have the NKP 1947 folio diagrams for freight cars in our Folio Book and it includes all the info on both 70 & 100 ton Dolomite container carrying gons:
http://www.quickpicbooks.com/Folios/NickelPlate/NickelFrt47_Psgr54.html
 
Here is the pertinent info from the book:
 
There were 70 ton & 100 ton dolomite cars. The 100 ton car is even one I put in the sample pages from this book. Because the measurements are not readable in the sample page (but they are clear as a bell in the book) here they are:
 
 
70 ton car � NKP 75050-75069 carried 8 containers per car and they were built in 1934 as D.E. Gons Nos. 71000-71674. In Sep � Oct 1943 they were rebuilt and renumbered and equipped with 70 ton trucks for container service.
 
Load limits in containers 136820 (not dolomite)
Load limits in containers 128640, 1072 cu. Ft. dolomite
Load Limit without containers 156700