Map of Spalding but what is the Date

These maps are part of Geoff Dodd’s archive and I think they are something to do with putting new electricity cables in. Someone has written in the names of some of the business. Can you add to this? Do you know the date? It shows the Mansion house where Herring Lane car park is today, The old corn exchange, buildings along the river front and it shows the house in Draper’s Place