from my past experience tuning turbo cars if you get hold of a cosworth T34 hybrid turbo and theres plenty about and they also come with a internal wastegate set to 11psi which is enough for the 325 and get a manifold and exhaust made up and get some bigger injectors with a walbro pump with a FPR and run a fmic thats the basics covered.
You will then nee a oil feed pipe and also a oil return and with T34 turbos there also water cooled aswel so you will need to sort that out which is simple really just take a feed from the coolent pipe going to the throttle.
You will need a good mapping company to setup the fueling and boost if you want to run a controller.
The standard head gasket will do just fine aslong as the fueling is all setup correctly.
This is a very long list its not as simple as bolt a turbo on and go weeeeeeeeeee tssssh bang
hope this helps