Can I replace my (fat) ps2 laser with my (slim) ps2 laser?

So I have two ps2's and the Fat ps2's laser wont load/read some games as it should, But my slim one will. Althrough my slim one is broken so I used its in my storage drawer (long story). Can I just switch the lasers on the two consoles so my working fat one can read every disc i have?

No, the lasers are different. You can find replacement lasers for fat ps2 on ebay. Very easy to replace.