I've got an Alan Jones front bar for my EF. Now I was just looking at the back, and I don't see how it goes on (i.e. what actually attaches it to the car).
It's been ages since I fitted the EL XR front bar on, but from what I remember that black plastic rebar thing bolts to the nose cone, and then that bolts to the car.
But I don't see how that black plastic rebar attaches to this front bar?

Photos:

see the 2 protrusions behind the number plate. They attach to the rebar. Looks like you will need to drill and bolt to attach. Do ypu have a front on shot?

either that or fibre glass some bolts to the inside as thats how mine came

looks similar from the rear to my front bar

I've got a fibreglass bumper on mine. I have 2 bolts at the corners that go through the guards, and I have a couple of screws in behind the number plate. It sits very firm so it's definately not going to fall off.