Freelander 1 A Bar/Bull Bar fitting advice

Hello all, recently purchased an A bar for my 99 L Series, I believe the brackets at the bottom attach to the sub frame bolts that I can feel inside the plastic bash plate. The two fittings on the side I assume are for bolts that go thru the plastic and attach to the metal bumper behind? Do you use normal bolts or riv nuts? Am I correct in assuming that's how they fit? Or will a course (large) self tapping bolt be enough? Does the bumper need removing or just drill through the plastic and into the metal behind? Appreciate any advice regarding this, I've checked the other historical threads and tried to piece tog ether clues! Thanks in advance!

Hi.
Try this.
http://topix.landrover.jlrext.com/topix/index
It has fitting instructions for all approved L/R accessory.

Thanks Slimboy, I tried the Topix a few days ago but the bar I have isn't on there. I believe the one I have is DA4111 and I can't find fitting instructions anywhere! It all looks pretty obvious but just not sure what the best course of action is regarding attaching it to/thru the bumper.

I think it's a Britpart product