iI have a saab t3 turbo, and i just bought a T3T40e turbo today.. They both have a 5 bolt exhuast flange My saab's turbo has a .63 exhaust housing and so does my t3t4...Im using a saab exhuast housing with a internal wategate... my question is can i use my same saab exhaust housing on my new turbo.....

 

yes you should be able to take out the center section and cold side from the new turbo and put it on your saab turbine housing so you can use the internal wastegate.
just make sure the exhaust wheel is the same diameter.