In looking closely at some photos of K-36 #484 in the 40's I noticed that the coal bunker extension had a 90 degree angle along the back like #488 did, rather than angled like the other K-36 tenders. See here (Photos from the drgw.org site):
This 90 degree angle shows up in photos dated through the 30's and late '40s.
Here is #488 in the '50s:
Did these locomotives swap out their tenders in the late 40's? You don’t see #484 with the right angle past that period and you don’t see the #488 with the right angle before that period.
Erik