Hai varun,
I'm planing to fix a Rear wiper cum washer in my Ritz but my point is ritz and swift rear wiper is fixed in rear Glass. i have done all wiring and washer nozzle fixed but can able to drill the glass? no one is ready to drill the glass.
Also note, rear defogger can't be simply fixed in the car as this power and heat load is controlled by BCM(Body control module) unit so you can't fix this just like it.