Not sure why it generated so much interest but as from the other thread:
That's a cage with the feet knocked out, the whole thing then slides over the rear seat area with a bit of brute force, so you can weld the screen bar through the doors, and the main hoop over the top through the rear window holes.
I don't cut any holes in the floor, as the cage has to come backwards somehow as it triangulates to the front struts, so you need put those bars in before the a-pillars go in place.
You can see the feet I use instead:
^Now sports a lot more diagonals and door bars mind
Means the whole cage can be made a close fit right from the bottom of the b-pillar to the front of the a-pillar and all the tube work between. Which allows lots of stitch welding directly to the chassis
It's a right bar steward to fit the thing with it being so tight, but I'd rather swear for a day extra fitting it and have it tight to the bodyshell, than have it floating in fresh air like a lot of off-the-shelf cages.