Hi Don, it sounds like you've got it handled now but in MoI that's called a "mutual trim" where you want each object not just to get cut but to also cut others in the same operation as well.

To do a mutual trim, you just select all the things you want to trim, and when Trim prompts you to select cutting objects you push "Done" or right-click at that point to signal that you are not selecting other cutting objects and instead doing mutual trim.

- Michael