Now updated with additional years:
Data from 2006 to 2018 was sourced form Haringey Council. Data from 1994 to 2002 was from the LondonDatastore. Earlier than that was from the Plymouth University report, cited in my second comment below.
Prior to 1986, the ward names were different. I don't think the boundaries and names of Haringey's wards were changed. To the east of Green Lanes the changes were significant, but I don't think much changes with the boundaries this site of the high street. I'm on the look-out for maps/data to evidence that.
And in looking for older results to add to my first graph, I found this chart showing borough-wide party share 1964-2010.
Two things strike me in particular. The first is that the Lib Dems seem to have gone from almost nothing before around 1990 to near-parity in 2006. That all got kiboshed post the coalition government. Secondly, Harringay ward seems to be a pretty good proxy for the vote share pattern across the borough.
This graph was sourced from London Borough of Haringey Election Results 1964-2010, Colin Rallings and Michael Thrasher,The Elections Centre, Plymouth University. The report says that results from the immediate post-reorganisation period (1965 on) were painstakingly, although not exclusively, collected from local newspaper reports. From the mid-1980s onwards the results have been obtained from each local authority by the Elections Centre.
Thanks Hugh. It paints an interesting picture. At first Haringey was two party Labour/Tory. Then the conservative vote collapsed and switched to two party Labour/LibDem. Seems we only have room for two parties at any one time in the borough!
I was surprised to read that thirty years before this graph started, part, at least, of Harringay was apparently solidly Conservative. This from Women, A Modern Political Dictionary by Cheryl Law:
"Harringay ward seems to be a pretty good proxy for the vote share pattern across the borough"
Does this mean Harringay is the Basildon of Haringey?
I've now found the data back to 1964. After the reorganisation of London local government on 1964/5, the Harringay Ladder was for the first time put into a single electoral ward. True to the habit the Council has never really lost,it sought to call our area anything but Harringay. So the Ladder that had previously been in North eHarringay Ward and South Harringay ward (Hornsey) and Green Lanes Ward (Tottenham) as put into a ward called Turnpike. It was renamed Harringay ward in 1978. In 1978, a certain Corbyn, Jeremy B. was elected to serve Harringay.
I don't yet have the data prior to 1964, but, I think this snippet from the Daily Herald on 2 Feb 1950 and the trends in the graph below suggest that we're probably going to find a Conservative majority seat prior to 1950 and perhaps a bit og changing hands between then and '64.