This institution has one of the most thorough and comprehensive collections of local history, in the area.

Since the City of Wyandotte is the second oldest (1867) city in Wayne County (only Detroit was incorporated as a city earlier), they were one of the earliest locales to have had city directories issued/published. Both their population and prestiege warranted this. The collection of Wyandotte City Directories at the Bacon Library is the most complete in existance, from the first volume in 1898 to the present. They only have selected, sporadic, years for the first 20 years or so...some years there were no directories published; others are just not documented with surviving copies.

I checked my copy (very rare) of the first directory from 1898-99, and found a "Mrs. R.F.Johnson h(=homeowner) 119 Fifth Street" no further info and no other Johnson's or Myers that fit your query.
My copy of the 1936 directory has no listing for a Richard Johnson or Mary Ann Myers.

Another resource is the microfilmed copies of the local paper, "The Wyandotte Herald". This paper was printed from 1879 to the present (as the Heritage Newspapers). While it is not COMPLETELY indexed, there are SOME indexed years by subject (birth, death, marriage etc.) They may have a reference to your family member in their index.... If not, you can always come to the Library, if you are local, and read ALL the issues of the years in question. There is a very well written column/page from the earlier years, "Local Brevaties", that holds a wealth of information.