NCR Sets 77 and 78

["Allan Brown" <ajbrown@easy.com.au>]

My records show that the four cars that made up the NSWGR NCR Set 77 (HCV
694, BV 931, RFV 918, HFV 924) all had four truss rod underframes.

However, the four cars that made up Set 78  were different  - as follows:
HCV 921 (2 truss rod u/frame), BV 485 (cantilever u/frame), RFV 693 (2 truss
rod u/frame), HFV 690 (cantilever u/frame).

I presume the cantilever underframes to be of the drop centre type, similar
to what was used on the SFX carriages. Can anyone confirm this please?

Allan Brown