How bout something like ... this.
Red = underground
Cyan = elevated
Yellow = at grade
Purple = unknown
I tried to use the route that would require the least number of buildings expropriated.
I only count about 37 properties that would need to be expropriated, and I bet most would not need to be torn down, they'd just lose half their back yards. Could the city actually expropriate just a say 20-30 ft of the back yard and pay the owners for the land if they wanted to remain there?
Also, arguably 36 ave to 60th ave could be at grade, at the cost of expropriating perhaps 17 additional small houses plus 1 medium multi family and 2 apartment blocks, or using the other side of 1st ST NE and expropriating 10 lots, only half of which would have buildings which would need to be fully or partially demolished (1st st could bend westward north of 40th ave to increas the ROW on the east side)
This could be an alternate middle portion: