[Angel Darkover]

I tend to use a slightly different method. It works similarly, but makes monitoring and observing (and remembering) much easier. I would create a custom advantage parent object and call it something like "Battlesuit Benefits" or some such. I would then add each advantage that is appropriate to the parent as well as the appropriate modifier to make them free. From there, I can simply enable or disable the parent as Armin spoke of. By taking this route, rather than modifying the equipment itself, it makes it easier to track down perceived anomalies - especially if the character file is handed to someone else, like the GM, who may not remember that such edits were made. It also ensures that the character keeps such elements should you need to do a resync.

Just to be clear, Armin's solution is precisely what you asked for, but this approach may be easier to manage, especially if you tend to use GCA directly (instead of printouts) while in gameplay as I do.