SVRy's wrecking crane was numbered 070. It had other work equipment that went with it numbered sequentially. Looking at the car accounts, it was on the basic inventory in 1916 so it predated the AFE's and any clue to when it was actually built. It originally had a locomotive type boiler that was replaced with an upright "Mundy" boiler. Date unknown, but possibly when it was set up with a pile driver in 1917. It had two vertical engines. This unit was retired in 1934. It appears that a new flat car 070 entered service in 1937 and was equipped with the pile driver as shown in the photo Taylor posted in 1939.
The 070 unit be it the earlier or later version, was probably not the Marion Shovel as it also was in the basic inventory in 1916 as a seperate piece of equipment. The Marion Shovel was built in 1913, serial #3142, had a capacity of 1 cu. yd. and was retired in 1937, sold to OLC. It's unit # in the SVRy roster of equipment was the same as it's serial # being 3142.
071 was the tender and tool car for 070. 072 was a tool and outfit car, probably used in conjunction with 070, and 071. 073 was a flat car noted in the roster info as "for use with derrick". Perhaps it was used as an idler in front of 070 for the boom to rest on.
There is a photo in R.S.&P of 17 being righted at Austin with the wrecking crane. The photo I am attaching is of tool and outfit car 072. The tender of the engine coupled to it appears to have been on it's side. I wouldn't be supprized if 070 wasn't nearby.