The AAZ and TDI model are intechangeable
Mine had a dent from the install and the local VW dealer wanted top money
I purchased both models ( AAZ & TDI ) from the VW Diesel website for under 25.00 for the pair and they are a good buy from this website.
I compared both of them to a new VW assy from Gile's ( 72.00 V.W.) and they are identical.
Iam still trying to find the correct harness clips that snap on the hardline coolant assy for my wire conduit for my oil psi / oil temp wire to my housing.
My dealer has ordered three different clips now at no charge and when they get the part # correct i will advise.
Gee-Bee