This video shows how to remove a shock spring, oil the cleaned jewel setting and replace the spring using tools modified to fit the type of shock spring used in the platform escapements for D3 practice and exam pieces.
The spring has to be turned 90° to release the spring. Using a modified hand removing tool with outer diameter turned to fit over the spring and hollowed out to a fine edge the spring can be removed without scratching the polished surface of the spring. the tool will prevent the spring from jumping out and possibly getting lost.
An alternative is to make a tool from a piece of pegwood.
Replacement is the opposite of removal.
Oiling the jewel setting after cleaning, turn the cap jewel flat side up and place a small amount of oil in the centre of the cap jewel. then place the jeweled setting on top. Capillary action will hold them together.
Then replace the jewelled setting and the spring.