My grandfather is also buried at Summit hill which is now listed as Cadillac Memorial Gardens East. Same year 2936 and same undertaker, Alex La Bell. It's located in Macomb county whereas Detroit Receiving hospital is located in Wayne County.
Unfortunately, they don't have their master cemetery list online. I've reached out to the Macomb County Genealogy Group to find out more about finding my ancestors grave at the Summit Hill Cemetery. If your still interested in information about this cemetery I'll pass on what I find out.
Alexander H. LaBell operated the (Alex) LaBell Funeral Home at 1378 E. Grand Blvd. from approximately 1930 into the start of the Second World War.
Cadillac Memorial Gardens East - 38425 Garfield Rd., Clinton Township MI - (586) 286-7500