Hi,
It was quite shocking to know that a Rs. 4.13 Lakh car did not coming with rear seat headrests. Yeah, I am talking about my brand new Maruti Suzuki Astar Lxi. So I went on a mission to get the rear seats headrest fitted anyhow. In this post, I have covered the reason for fitting them, the way I sourced them and more importantly the fitment and the look thereafter.
The material and tools you would need are:
1) MDF Parcel Tray which atleast 2" thick
2) OEM Headrests
3) 10mm Drill Bit along with an appropriate drilling machine (or one may also go to
a turner/metal workshop for a hand drill and Tap Die)
4) M10 nuts x 4
5) Tap Die for marking threads on the Headrests' metal rods
6) WD40 (Lubricant)
7) Lots of dedication and stamina!
8) Foam Pads 7" x 7" of 2" thickness
9) Vernier Calliper or Metal Scale
Cost of Material
1) Astar VXI/ZXI rear seat headrests - Rs. 517 each
2) 10MM Drill Bit - Rs 40
3) MDF Parcel Tray - Rs 350
4) M10 Nuts - Rs 2 each
5) WD40 - Rs 30 for the small spray can
6) Labour incase you do not want to buy the drill bits/drilling machine and Tap die - (Rs 10 for drilling four 10mm holes, Rs 20 for threading the headrests' metal rods.)
7) Dense Foam Pads - FREE as I requested a custom mattress shop owner to give it from the wastage!
Background:
I was lucky that I fitted an MDF 2 inches parcel tray to house my speakers. Since my Astar Lxi did not even come with a provision to insert the headrest, which I could buy myself from a MASS. Why did I so badly want rear seat headrests? They provide extra comfort, enhance the incabin feel and my LXi looks like a Vxi.

I sourced my headrest from a MASS named Zenita Automobiles at Andheri Mumbai, who in turn placed an order on my behalf at Maruti Gurgaon. I had to wait for 12 days to get my headrests shipped to Mumbai. I finally got a call from Zenita and voila!, I had my headrests.
Method
I measured the exact distance between the plastic brackets till the first metal rod using a vernier calliper and marking from an Astar Vxi parked nearby. The driver of that car luckily allowed me to take measurements.
I had earlier removed the speakers from the parcel tray.
Once I had the measurement, I drilled two holes accordingly keeping in mind that the drill doesn't end up tearing the MDF and damage the cloth on it. I replicated the same for the other side.
Option 1
Drilling 11MM holes so the headrests move up or down freely.
Using a tap die (for threading over M10 or 10mm bolts)
Fitting nuts both above and below the parcel tray in order to secure the headrests.
Option 2
Drill holes which are 10MM in diameter; the headrest rods fit in tight and will have to be hammered so they fit in tight.
In this scenario, one need not mark threads on the headrests' metal rods or fasten them with nuts.
I preferred option two as a tap die was not available but I did make it a point to list the method over here so people who have access to the tools can use this more effective method.
Once the holes were drilled, I lubricated the holes with grease/wD 40 so the headrests would go in smooth. However, I did have to put some effort to insert the metal rods in the drilled holes.
The downside to this method is, it gets a little impractical if one needs to adjust the height of the headrest every now and then as he would need to hammer it. Over here I wanted them in a Fix position.
Once I aligned both the headrest, I tipped all the four rods with small bits of foam, so a person using the boot wouldn't end up wounding himself due to the sharp edges of the metal rods at the bottom.
I fitted the speakers back onto the parcel tray and voila it was a job well done.
Incase you choose option 1, then you would need to drill four 11MM holes instead of 10MM. If one doesn't have access to 11MM drill bits, then one may file them carefully.
Now mark threads using the tap die all,the way up, on one rod each, of the two headrests. This is to ensure that one rod of the headrest moves freely and the nut on only one rod needs to be adjusted for adjusting the height and securing the headrest in the MDF tray. The procedure that follows is the same as in option 2.
The difference in the original position of the headrests (where they support your head) is a bit different as the headrests are about 1.5" away from the OEM's provision. To fix this issue, I have purchased dense foam pads which are about 7" x 7" with 2" thickness; these dense foam pads have been cut in an angle similar to the one provided by the OEM's headrest arrangement and are concealed behind the headrest covers, which I got along with my Art leather seat covers.
Please make sure you avoid using a sponge; it will not provide the firmness to your head and will compress over a few days.
So guys, this is how the 1.5" problem got solved! If you are unable to source foam pads, you may buy those neck supports available at accessory shops, but I do not like the look.
I have posted pics which will help in illustrate how I fitted it. So guys please do PM me if I my instructions are not clear. I shall wait to hear from you. If you wish to view photos of my Astar Lxi: the thread is named "Experience a Star".