Uninstall the screws here which installed the fiber cable connected laser source.
(Please take care of the screws, parts screws are different. So, it is best to put them separately, you can take a photo before taking off to know how to install them after getting the source back.)
Take off the back cover.
Take off the cover on the laser arm. (Pull back first)
Take off the screws here (Screws can be left on it after taking off the round part optical isolation so that screws will not be confused with other screws.)
Take out this part very carefully with the below steps:
Take off the black cover on the yellow fiber cable. Take care of this yellow fiber cable.
Take off the round part from the hole.
Find something like the below picture to cover the top. If not, please find plastic like the following photo to avoid dust getting in. And then packed it tightly with adhesive tape.
Plastic to cover the top.
Take off the screws on the port which the fiber cable passes through.
Loosen the plug on the laser source.
Take off the cable which connects with the laser source. It has some letters on it.
Take off the screws on the laser source with this tool.
Take off the laser source with the optical isolation.