Hi Akshay or others in Delhi who may be interested,
In the event that sodmebody else hasn't done it already, do try to digitize these boundaries and put it on github.
I'll encourage you to find a college department that's into mapping, find a room with projector and many plugpoints or computers, and do a map-a-thon with a class of students. Make teams of two or three each and have them do a different map each. Keep a google spreadsheet open that tracks each ward and wh's doing it and final link. I had done this with a class of planning students in Pune a couple of years ago with develpment plan maps and after some initial walking-through it went quite well.. the students themselves got interested and engaged in the activity.
Things would also get much easier if there is an image or pdf somewhere with all the wards combined. I guess it's not there in the govt site but might be there elsewhere. It would probably be lower resolution and less accurate but would serve the purpose if you know your streets.
I know two ways : One using GeoRefencer in QGIS alongwith a plugin that imports a map tile layer (recently did
Pune's new wards using this way), and another using a web based tool called mapwarper (had
warped development plan maps with students using that way).
Here's a link to a guide on the second method. For the first I'm sure a web search will give some walkthroughs.
http://datameet.org/2016/08/12/guide-on-digitizing-static-maps/-Nikhil VJ
Pune