The Donation land claim and the residence parcels of two members of the Newsom family were located west of the Pudding River River near Mt. Angel Oregon and in section 17, although their land parcels overlapped adjacent section boundary lines of 3 other sections. The DLC you mentioned was 320 acres,so half a section. An easy way to envision this is a rectangle, half mile by a mile wide.
Based upon viewing the surveyors map of 1852 it would seem that the road name evolved from the surname of the occupants, Newsom, and their large cultivated parcel in the early day.
The approximate location of the residence of D. Newsom appears to have been generally between Prarie Creek and the Pudding River and more specifically very near or at the intersection of present day N Howell Prarie Rd NE and Nusom Road NE (on today's maps). This location is identified by conversion of the legal description of the donation land claim range township section information, and comparing this with the matching 1852 surveyor map to confirm the site.
Interestingly, The surveyor map shows the residence and the cultivated farm parcel of D. Newsom and also J. Newsom.

The present day Nusom road does not run directly east west and runs somewhat diagonally at this location. My guess is this is due to the evolution of the road from running across the private cultivated fields.
The 1852 map shows a north south wagon road running near exactly north-south for a distance of about four and a half miles just west of the Pudding River and terminating at the home, the residence, location within his land, of D. Newsom. From this point that road then runs near due south 4.5 miles where it intersected a wagon road leading to Howell Prarie running east-west.
Driving south from the 90 degree bend of today's Saratoga Drive NE thence south along N Howell Road NE to Nusom Road would put your vehicle driving over these two land parcels of Newsom members and very close to both historical residence locations. The land today is agricultural and cultivated, and the parcels seem to have been split to various owners and-or certainly various crops.
Hopefully my description helps you to identify the parcel location to some degree. An easy aerial view is on google maps, for example.