You won't have a problem from rain. I've had zero problems with the Mars in the auto cashier which has no kind of shield on it at all, and it's not even an upstacker.
Perfect. I tried to install one today but it turns out that the mounting posts for the bill acceptor are short and I need to extend them. Any idea what the standard size is for the mounting posts for the bill acceptor. All bill acceptors use the same posts, so it should be the same size.