How do i get my speaker on to the speaker bracket?

No brackets are necessary...I believe you are talking about replacing the rear speakers located in the rear wondow shelf...Of course the speakers mount underneath the window inside the trunk...You can remove the rear seat and pull the interior trim back to view the top side of the speaker mounting...The opening is already cut for the 6X9 speaker...You can mount the top underneath the window cloth material like the factory did, or no need to remove the interior cloth if you use new top speaker covers, usually come with the speakers. Hope this helps.

http://products.bose.com/pdf/customer_service/owners/og_901.pdf

They don't actually require brackets. Page 7.

I am guessing but I'm pretty sure the arrangement on our 747i will be the same:
Look in the rear for four brackets each with two 90 degree angles. Each of these has two Phillips screws at the speaker enclosure and two above it attaching to the set itself.
Removal of these brackets should allow the removal of the two speaker enclosures.

big red
they allways have a screw in the back you just tighet it and level your speaker

Unfortunately there are two standards for the pole diameters. Some of the smaller poles have caps to accomodate the larger brackets. First thing is to measure what you have for poles and the two sizes of mounting holes. Many of the mounting bosses are standard and available online here is an example:

http://www.amazon.com/Speaker-Cabinet-Metal-Stand-Mounts/dp/B0035AJTL8

you won't have to do any cutting the brackets should help fine

You don't want to fit that - it's the factory amplifier for the rear speakers (the rears are amped, the fronts are not). You need to run new wires from the head unit back to the new rear speakers so that the speaker-level outputs from the new head unit are used to drive the new speakers.

Pop the bottom front cover off (that is over the speakers) first. This will expose 2 brackets that hold the moulding around the screen in place. Un-screw the brackets enough so you can get the moulding off and take it off. Once the moulding off you will see the brackets that hold the actual screen in place. Loosen these brackets and VERY carefully remove the screen (it will wobble and bend so I would recommend 2 people do this). Lay the screen down on a soft surface that will not scratch it. Clean and re-install screen, tighten brackets, re-install moulding, tighten brackets and pop the speaker cover back on.

Polk in the US are sending me a replacement pin. What great guys they are.