I answered this for you over on the MGZR.co.uk site as well, but its here for anyone else that may also need the info:
There are actually FOUR bits needed to make up the complete mounting kit and they will cost you in excess of fifty quid with VAT.
When they arrive, they don't look like the ones in that picture either. When I get chance I will take some pictures of mine for you and post them up.
Two brackets bolt to the changer unit and slid into a carrier bracket that is also made up of two brackets that bolts under the N/S of the parcel shelf area
They were a bitch to get into stock last year when MGR were working normally. I would expect them to be almost impossible to source now.
I made some brackets up in the 1st instance to hold my changer in place and if I had known how much of a pain in the backside it would be to get the original brackets together, I would have just stuck with the home-made setup.
I made do with just three of the bits in the end and my changer is pretty solid (they still took 6 months for my dealer to get into stock)
The part numbers and prices on my invoice (cos they are a real bitch to ID on the EPC) are:
R XQU100700 Main Support £9.70 +VAT
R XQU000120 Side Bracket £14.44 +VAT
R XQU000130 Side Bracket £14.44 +VAT
That lot adds to £45.33 with the Governments bit. They will be enough to hang the changer securely.
If you do want the other bracket add another £15+VAT to the total. I didn't bother.
Those two side bits at 15 quid are the real piss take, they are just two pieces of bent metal about 10mm by 50mm.
The bulk of the carrier support is the 10 quid bit. Thats the bit with most work in it, so I dunno just how they calculate their prices.
If you can find someone with a BRM that doesn't use the boot stacker - the mountings were a std fit in there I believe,