Note: The boots shall be installed dry (Do not use any lubricants), especially when installing high temperature (Blue) dust boots, extreme caution must be exercised from avoide contactiing with brake fluid, brake greases etc., or they will attack the boots causing pre-mature failure like this Focus RS installation.
https://www.focusrs.org/threads/brake-caliper-dust-boots.120830/post-2253378

This brake grease attacks blue boot in contact.
