Late HL hoppers...

[NW Modeling List]

I think your first assertion may be closer to correct, that the entire HL class was built with the fishbelly side sheets. Like other Company images, the "late production HL" image in Mr. Dow's book is suspect. 
Grant Carpenter


Please explain further... I see nothing 'suspect' about the image.  Car number is in a legitimate HL series, isn't an H9 rebuild (note the one piece sides... when the fishbelly HLs were rebuilt to H9s, they got two-piece sides... the late HLs that were rebuilt retained their original one-piece sides, and Portsmouth certainly didn't paint any of those in 1952).

It's not any other earlier two-bay class or rebuild from that classclass (i.e, HA, HB, HBa, HK, H5, H7, H7a, H8) as the side angle is in line with the end angle and both are above the sill... a trait only seen on HLs and H9s.

Many classes underwent revisions to lessen cost and simplify construction or provide alternate construction methods... many time without a new sub-class.

Robb Fisher
RFDI