This really is one of those things that I'd have to be there to see. However if you look at that bearing you will see it bolts to the housing, so the axles cannot come out if assembled correctly. If the axles are indeed too long it's a simple matter of machine triming off the ends of the axles and extinding the splines, a process that is both inexpensive available in most places local. I usially cut them to give about 1/8 inch clearance from bottom out, without the bearings. This is usially the time to press on new bearings and replace the little axle
oil seal inside the housing too, keeping it mind that most drag race guys don't put em back in, and the jury is still out if they are even needed at all. Don't let the guy that trims your axles talk you in to hardening the ends. On street cars this usially only makes them brittle, if you were to curb a tire the axles will be more to likely break, usially at those same splines. This is because hardend ends only add rotation strength to the spines, ok for drag only cars, not ok for street cars.
Ron Shockley