I checked in a box that size once... having put a rope handle on it (it would have been very awkward to handle without that!)
The only comment the check in agent made was one of delight.. "You put a HANDLE on it!"...
I doubt anyone could eyeball the difference between 62 and 67... so I doubt you'll have a problem.
As always, and as already mentioned.. it IS oversized.. so if you don't end up paying, smile!