Go to the USAHEC website (https://arena.usahec.org/web/arena) and do a search for Howard Madaus Collection. Most of the line drawings are in box 32. Click on whatever you want to look at and select “Show linked records.” Click on what you want in what comes up and select “Show linked records” again. Eventually you will reach a link to a .pdf of the document. The collection is a nightmare to find anything. Took me about 3 hours to find 5 scans I was looking for and that was using a document provided to me by the USAHEC called the Madaus Collection Finding Aid.