Looks like Minquan Road, Lane 237 (民權路237巷) is now Dahe Road (大和路). Anyway, that's what the clerk at the check-in desk at the Yadian Commercial Hotel (雅典商務旅館) on 3 Dahe Rd. told us. (She was very helpful even though we didn't want a room.)
So from what we could gather, the Japanese-style house that used to be at No. 7 is now this:
(A parking lot, that is, not a car.) Oh well...
(Note to self: one of these days I ought to standardize my romanizations...)