Needed: OEM cat c theft deterrent solution; already had 1 stolen

all. I know there are different after-market solutions out there on the Net, but I can't find any really good testimonials by mechanics, police, tow truck drivers, etc. (e.g., we've installed 300 of these and only had 1 come back, etc. ).
It needs to be an OEM solution due to complexities of how I'm getting loss covered. Shop won't do welding. They said if they can find something they can bolt in that might work. But needs to be something they can order from the dealer. Called 1 dlr and they said they'd installed 10 anti cat c theft shields (Miller). They say it's 2 hrs labor. Tow truck driver said he's seen thieves get through the shields.
What is the best prius/Toyota/OEM solution?
At first I thought painting/engraving would work, but shop has no idea. And I'm kinda stuck bc how am I supposed to paint/engrave once it's already in car?
Any help appreciated!

 

Thanks, Bisco.
OK, I'd like to refine this post -
1. Has anyone had cat stolen despite having Miller Shield installed? And which kind of Miller Shield was it? Toyota dlr nr me uses aluminum kind.
2. Tilt alarm -- how much do they cost and how much to install? Are these the same as the very loud alarms that would make it impossible for a thief to complete the theft?

Also, can someone please tell me how to make a basic post that everyone will see -- not just in a specific prius generation forum? Or how to edit a post? I used to be able to post//edit w/ease, then somehow the whole site changed . . thanks!