We started recording 1940 U.S. census enumeration districts (EDs) for our closest relatives using Stephen P. Morse's very helpful website. Dick's parents and paternal grandmother lived in Cleveland, a city for which the EDs have been indexed. To find their ED we used Obtaining EDs for the 1940 Census in One Step (Large Cities) and with their cross streets quickly got the number. My great aunt in Lakewood, a nearby suburb, was equally easy. My parents lived in North Olmsted, a small town/suburb, that only had two EDs. The written descriptions show the town was divided by the main east-west road so all I needed to know was whether they were north or south of it.
We couldn't find his maternal grandmother as easily. She was widowed in January of 1939. We knew that she moved, but not when or where, or if more than once. Luckily the Cuyahoga County deeds are all available online. A search for her name in the appropriate time frame turned up a deed from November 1939. At that time she bought the house where Dick remembers her living. It is highly likely that she moved in before April 1st of 1940. We had to add several street names, looking at a map, before we could narrow down her ED, but we think we are ready for all our closest relatives in this area.
Now, it is just a little over 32 days!