I would like to order an under-drive pulley for my M3. My car is a 05-2008 build according to the data plate on the driver door sill and is equipped with DCT.
My challenge resides in picking the right pulley/belt combo. The build date of my car is just a the threshold of when the belts were changed from single sided to double sided. The Turner site specifies that all models produced May-08 and up have the new belt while Dinan says all model June-08 and up have the new belt. To make matters more complicated, Turner also specifies the new belt for all DCT cars regardless of build date.
Is there a way I can visually determine this myself by looking at the belts on my car

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Any help/insight from vendors would be greatly appreciated

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