I own a 1997 Saan 9000 CSE 2.0t and I want to upgrade to a 2.3 full turbo will the engine fit

Why change the engine, get it tuned up, it will cost you a lot less then changing the engine, which will fit if you really want to go that way. You may need to do some modifications etc to the engine mounts etc.
P.S
Check the website maptun.com. or bsr.com. They can help and guide.

Hi
Not worth the hassel
You have to have different exhaust and ecu as well

and for very little gain to be honest no much difference in performance

And you will have to notify insurance in case you have accident if you dont inform and they find out they wont pay !

The gearbox may not be compatible with this size engine. The bigger the engine the higher the gears have to be in the gearbox. You may not get anymore speed due to this.

Stop asking for trouble because it is cheaper and better to sell yours and buy the type you want which is factory made than to try and modify your one.