There were no instructions with it so I thought i'd document the installation of this into my car. The roll bar is a fairly basic but robust design which mounts onto the seatbelt towers and into the rear bulkhead with reinforcing plates on the other side of the chassis.
I only remembered the camera part way through but the first bit is just removing trim etc.
Tools needed: Axle Stands, Heavy duty drill with sharp quality bits, file, allen keys, screw drivers, spanners and crescents, pop marker, vacuum cleaner, primer.
People needed: 1 with another available
Time need: Around half a day
Steps
Remove standard strengthening bar behind seats (if fitted).
Remove hardtop latches X 2(if fitted)
Remove trim at top of door X 2
Loosen door scratch pads by removing the rear most screw and then removing rubber rear door seal x 2
Unscrew demister plug from seatbelt towers
Carefully remove parcel shelf carpet fasteners (to allow access to rear bulkhead carpet fasteners) by wiggling each out.
Carefully remove rear bulkhead carpet fasteners and carpet.
Remove seats (its possible you may be able to install this with them in if your drill is very short but it is probably easier just to remove them). Don't forget to unplug any accessory plugs from seats (i.e. seatbelt warning lights)
Remove seatbelt tower trim X2
You should now have a clear view of the rear bulkhead and seatbelt towers- These are the two mounting areas for the roll bar.
Jack your car up and place on axle stands or use another failsafe jacking system.
You should see two rubber grommets on each side of the rear bulkhead- These are holes into which you need place the first two bolts to locate the roll bar. Remove the grommets and place the roll bar so it lines up with these holes and then place a bolt in each.

Take the reinforcing plate and if you are very flexible you may be able to sit and rotate the bolt inside the car to take the thread while holding the plate (under the car). If not, use another person to help.

Do this for each side and do up tightly to locate the rollbar.
On my car, there were also existing bolts on the seatbelt tower with fasteners for the tonneau cover- I used these as extra location bolts in the middle of the three pre drilled holes on the roll cage rear mounting plate.

Now carefully mark the centre of each remaining hole using a pop-marker.

Drill pilot holes using a small drill bit ensuring all holes are centered as best as possible to the holes on the roll bar mounting places. The steel on the suspension towers is very tough so ensure your drill bit is sharp and of good quality and use lubrication if necessary.

Now drill the larger holes using a bit one size smaller than the bolt thread and ensuring that the bit only drills through the chassis steel and not into the mounting plate behind it. Use a file to finish the drilled hole as necessary to insert and tighten the bolt to the backing plate.

Repeat this procedure for all bolts and ensure all bolts can be tightened properly (although we will have to remove them all at the end anyway to refit the seatbelt tower trim) *

* on the left hand seatbelt tower on my car there was a mounting point for the heated rear window plug which gets in the way of one of the mounting bolts. You may need to chisel off the small existing nut used for this mounting point in order to fit the roll bar nut.
Once all bolts have been installed and checked remove them and the roll bar. Clean any shards etc from the drilled holes and spray any bare metal with primer or other protector. Vacuum any metal shards out of the car.
Re Install the seatbelt tower trims
Re install the roll bar by fastening the bolts on the lower mounting plate first.
You will now need to drill through the plastic of the seatbelt tower trim to insert the upper mounting plate bolts and then install these bolts.

Ensure all bolts are torqued correctly.
Reinstall other trim and rear bulkhead carpets- The carpet should fit over the roll bar and conceal it- I also took the opportunity to shampoo these carpets and clean under the seats etc.
Reinstall seats etc, lower off axle stands and ensure all tools are out of the car.
Done!
(pics to come after the car gets a clean!)