Previously, I was changing each dataset/raster to the same coordinate system by going through properties, XY Coordinate System. This was not working, kept everything looking like they were in feet, but still displayed the same meter dimensions.
In the last hour or so, I changed all coordinate systems (using the Project tool in Catalog) to the one I want, which is in feet. I brought all my newly-projected feature classes, etc. into a blank .mxd, and have the same outcome as before.
The same main still measures 165 units, it did not get reprojected to the ~254.2 feet as I needed it to. The aerial, the .tif image in the background, and all feature classes are in the same CS, and verified that the data frame in the .mxd is in the same CS.
CS of sewer dataset/feature classes after Project tool was run:
CS in the data frame from new .mxd after bringing in newly-projected feature classes:
Map units in data frame (not manipulated):