And please check if anybody used/bought the temporary import successfully on the border that you will be using. For example, it would suck if you come from Pakistan and it does not work out, would be awful to get stuck there.

Edit: But now that I wrote this, I realize you should also have a Carnet for Pakistan and India if you take that route.

A friend of mine, travelling in a PK registered vehicle, entered Iran at Mirjaveh with no carnet.