I don't think a standard 4AGE pressure plate will cope with a W57.
From what I have seen, the throwout bearing and input shaft on a W5* box is bigger than a T50. So you may run into troubles trying to use these with a pressure plate designed for a T50.
What sized flywheel are you using? From memory some form of Hiace uses a 200mm flywheel and W5* box (well a G5*, but they arer the same as far as this matters).
Best bet is to talk to a clutch shop.
Hen