I used fiamma mountings that are made for a T5, unfortunately they came from Italy and were designed for mounting on the right hand side of the van. Luckily I was able to drill out the rivets and re-rivet them in the mirror image to fit the left hand side. Probably if you source them from fiamma England they will already be for the correct side. I made nylon spacers at the time, but later I discovered that they were making the spacers and supplying them with the brackets.

Here is the link: Fiamma F45 awning bracket - VW T5/T6 (UK version) - Everything Fiamma

Here is a link to a few photos of how I mounted mine: Awning - Google Photos

Depending on what awning you use you may have to make further modifications to make it fit the backing frame of your awning.