Ben,
found some better info in DSG-II,page EMD-127.
Rock Island -1 was the Talgo Jet Rocket,it never was a Demo,
built for R.I. and went directly to them about 1956.
it Originally had a Blomberg front truck,not sure if changed to
a Flexi-Coil later on ?
retired 1966 and Scrapped.
Aero Train 1000 operated NYCity to Pittsburg during 1957,sold
to R.I. as #-2,this was on PRR.
Aero Train 1001 operated on NYC,Cleveland to Chicago 1956.
then went to Santa Fe 1956.
then went to U.P. summer of 1957 as the "City of Las Vegas".
then sold to R.I. as #-3 later 1957.
1966 R.I. retired 2 and 3 they went to the Green Bay Museum
and St.Louis Museum,they should still be extent.
am now thinking the article was in Rail Model Journal between 1995
and 2000 or so.it was mainly focused on the Bowser release of the
Varney Aero Train,but memory could still be faulty on that ?
some of the pics were in Color.
one of the Diesel Demo books should be of help also.
Spikre