It is quite conceivable for a unit to be built as a 65-ton and ballasted to 80 ton.

I also notice that the owners of that locomotive have given up on the "wet" in-frame fuel tanks and fitted an external tank.

The switch panel across the top of the instrument panel has the look of a retrofit. In fact the controls on that panel are the exact 10 switches (and 2 start switches) in the location sousakerry spoke of. (headlight dim/bright appears to be consolidated on the left two switches, presumably center-off: good luck educating your crews on that one!) It also appears control and (fuel pump?) was upgraded from a plain switch to a breaker. Not sure on fuel pump; my understanding is they did not have OE electric fuel pumps.

Our 110 ton GE (not to be confused with our 80 ton GE that I spoke about in my earlier post) has a similar switch panel and breakers. This particular unit was built in 1967:

Photo of the panel (click on the photo to enlarge):
https://goo.gl/photos/mpTvJ2QLYQjUtpSB8

http://www.rgvrrm.org/about/railroad/rge8/index.htm

The second breaker is an Aux. breaker. You are correct that these did not have electric fuel pumps. The diesel engines have Cummins PT pump/governors.

I read someplace that the main spotting difference between the "short frame" 65 ton and 80 ton models was the thickness of the deck plate.

WK&S 734 is 65 ton
http://www.railpictures.net/viewphoto.p ... 16&nseq=14

USAF 1655 is 80 ton
http://www.rr-fallenflags.org/usa/usaf1655dsa.jpg

It's rather subtle, but the 1655 does appear to have a thicker deck plate, The one in your photo appears thicker as well.

With steel at 500 lbs per cubic foot, it wouldn't take much of difference in deck thickness to constitute 15 tons of weight difference.

JR