My calculations say a proper 9' 10" truck would be 7/16 in. longer which seems about right when comparing a B&O AS-16 photo with my model, shot at a similar angle and aligned by body seams. It's off, but still looks ok to my eye especially with the larger RS-27 fuel tank between the trucks. You can also see the extra body height MTH gave their model to clear the can motor brass flywheels.
I did a CNJ / B&O repaint ( paint out the B&O identification (TCP-352 Wabash Blue, not B&O blue) and put on a Central RR Company of NJ logo ) the way the CNJ did with the tired Baldwins, FM, Alcos, and EMDs it received from the B&O when it needed motive power during receivership. Bob Wilt photo below.
The CNJ didn't get any AS-16's (#904 was sold to Peabody Coal ) but the they did repaint one of it's own similar RS-12s (and other engines) into B&O blue and yellow in the hope the B&O would merge with them. Allan Roberts RS-12 photo below. Not as good as a green w/ toothpaste stripe paint job I would like it to have, but better than the solid green version.