Repairing my kenwood multi disc changer?

Greetings All,
I have a Kenwood DV5050M 400+3 multi disc changer the laser PU unit has just gone up. I found the PU Unit readily available on the internet, if I order the part online in an attempt to change it out myself does this part need some sort of calibration after install or will it be ready to use upon installing the new part?

Thanks in advance for any and all information you can provide!