Tuscan GG1s would have pulled the modernized P70faRs on the long-distance trains to Harrisburg and would be a nice fit for the Tuscan GG1. I have a set of 2 rail P70faRs and they are very nice cars. Add a Weaver (now Lionel) B60b and perhaps an MTH R50b express reefer to the front and you have a nice secondary train.
Often the P70faRs would run with streamlined equipment during the early 50's and could make for some pretty interesting trains where you have the heavyweight head end cars of the PRR and other roads with a mix of streamlined Tuscan cars such as the P85 streamlined coaches, diners, various configurations of sleepers, and Pullman Standard Heavyweight 12-1 and 8-1-2 sleepers. Do an online search for PRR images and you will see these types of trains under wire. While the majority of the GG1 fleet stayed in DGLE (green) colors, Tuscan GG1s would get the call to pull these trains as well.
The original GGD P70Rs are pretty nice also and would be accurate for Clocker service on the NY-DC runs.
One thing to keep in mind is that while the 10 GG1s that got 5 stripe Tuscan Red were originally painted to coincide with the introduction of the Congo cars, in reality, the first GG1 on the ready track at Sunnyside got the next train assignment so there are no hard and fast rules as to what GG1 pulled what train after the initial photographs for marketing.
