One GP35 was rebuilt by SP as a prototype to draw up plans for outside contractors, that locomotive became 6300. Locomotives 6302-6323 and 6353-6361 were rebuilt by Morrison-Knudsen, and designated GP35E. Locomotives 6324-6352 were rebuilt by the Canadian National and designated GP35R.

When SP's GP35 fleet came due for overhaul, one GP35 was rebuilt by SP as a prototype to draw up plans for outside contractors, that locomotive became 6300. Locomotives 6302-6323 and 6353-6361 were rebuilt by Morrison-Knudsen, and designated GP35E. Locomotives 6324-6352 were rebuilt by the Canadian National and designated GP35R.

Between 1977-1979, the SP contracted with both Morrison-Knudsen and the Canadian National to rebuilt 60 of its GP35 locomotives: The 31 units rebuilt by M-K ( SP 6302-6323, 6353-6361 ) were completed between October 1978 and November 1979 and classed GP35E. The 29 units rebuilt by CN ( SP 6324-6352 ) were completed between January and December 1979 and classed GP35R.

The following is taken from an email written by Steve Forrest who worked with Henry. " It was with great sadness that I learned of the passing of Henry Gulhstorf, former Kentucky St operator. When I first started hanging around Ky St, Henry was the night (11p-7a) operator. While I had met Benny Jones, Bill Gray, and Jim Bondurant (as well as all the Frisco operators who used to share the building) it was some time before I ever met Henry. Later when I went to work at Ky St on the extra board, I had the pleasure of working with Henry for many years. I would suspect if you interviewed all the crews that ever came across the bridge on the Cotton Belt, Rock Island, or Missouri Pacific, it would be unanimous that Henry was best who ever worked the job. When he worked third shift (by choice) he often could be found working on TV sets in between copying train orders or lining up moves on the CTC board. One of Henry's hobbies was TV repair, and the relative quietness of third shift provided him time to do this. When Benny Jones, first shift operator passed away in the late 70's, Henry decided to take the first shift job, which he worked until he retired. Henry was offered dispatching jobs by the RI, SSW, and MP, but always favored Ky St, altho I think he once came close to going to the Rock Island office in El Reno, OK. Henry began his career on the Frisco in Missouri, working train order offices all up and down the line between Springfield and Memphis. I can't recall if he ever worked the Briark office (altho Benny, Jim and Bill Gray did), but I don't think he did. Henry was alway good for a railroad story, and with his passing went a lot of great railroad stories and history. He was one of those people who you never heard anything bad about. I remember Rudell Wilson, long time MP MofW foreman, goodnaturedly calling Henry "The Alien" because of his German name. Henry would just smile and call Rudell "Redneck." Great memories for sure.