Dam that sucks dave, But like sneakin deacon said you should just get a couple red head cement anchors and make an anchor point. All you would have to do is buy the anchors maybe 15$,rent a bulldog cement chipper 30$ and fab somthin up , it would be the cheapest insurance you have ever invested in. 9 times outta 10 if you make it complicated for the thief they will just move on to the next dum dum two blocks away.