So, it's safe at .030 but not safe at .040? Bull fuckin squat rock!
Lets break this down. .040" is .010" more than .030". That equates to .005" PER side on a round bore. If it's unsafe at .040", it's unsafe at .030. .005" more thickness ain't gonna be appreciably stronger. I would bore that thing .060 and not think twice about it.
Looks like a good alternative to an overpriced crate motor. I would still inspect each and every molecule. But it looks nice.