I don't think any original drawings of the building or related facilities exist. I did quite a bit of work involving the old DL&W and could not find any resource at all that even gave s hint that any drawings might exist.
As for Not original drawings I made a set of the main passenger building itself only as a college study course in 79. I have hundreds of photos of the entire interior I took at the time as well. The drawings are ink on velum and rolled up in a tube, I still have them but they are brittle being over 30 years old now. I think my pix are all slide or negatives, I don't think I made a lot of prints, I still have all the slides and neds stashed away somewhere.
Someday I plan to get teh drawings transferred to CAD and offer CD discs with the plans, photos etc......doing this is not even on my priority list, maybe I will get to it within the next 5 years anyway. The drawinggs I made were done using not only photos but I spent many many hours measuring the building from the ground to the attic. I did floor plans, elevations and 2 cross section drawings ocv the building 10 or 12 pages of drawings. The plans have too much detail on them and are a little hard to read in places, CAD would be a great assett as the drawings I did were all manuually created and I was under a deadline to complete by the end of the semester so not everything lined up. aving CAD I can put in the exterior walls and openings and add the vertical columns and load bearing partitions and those will remain constants through all the other views and I can build in the details from there. When I made the originals I had to make compoimises from one sheet of drawings to the next so CAD will help fix those irregularities.
The elevated line to the coal dock was long gone byt the time I started to visit the DL&W in 78. Since the trainsheds were supposed to be saved by NFTA I did not do drawings of them but I do have photos. I used to pull pieces of broken NKP and DL&W china out of teh dirt and ballast in the trainshed, managed to glue together oms complete caucers and a cup or two.
I am pretty certain no origianl drawings exist as the NFTA and their demolition contracted came to me fror prints of teh drawings I made as an aid in demolition. They told me flat out that no drawings existed, only the ones I had made. Since demolition of the building was inevitable anyway I provided copies and got some kind of compensation that I have long since forgotten.