My electrician nephew said that the shunt is on the negative side so it won't be hot. If you accidentally ground the negative side nothing happens; that's why negative posts on batteries are left uncovered. If you ground the hot (positive) side life gets interesting in a hurry.
So I'd assume (and I'm sure you know what ASSUME does to U and ME) the shunt would work when hooked up to the positive side but you'd just need to put some kind of protective cover over it.