Pete, you can cut a few mm off the end of your axles to get them to fit. Some G series axles have different lengths. If it won't fit in by only a few mm, cut a few mm off with a cut off wheel and clean the splies up with one of those small trianular profiled files. Don't cut any more than about 4 to 5mm off. The driven splines on your axles are a few inches in length. The diving splines in the diff are only an inch or so wide, so taking a bit off the end of axles and 'sliding' them in further makes no difference to operation of the diff. It will then fit properly. If your axles protrude more than half an inch, you must have much longer axles in which case you'll need diff ones from a diff model hilux/hiace etc. Also, somtimes only one side doesn't fit, so you will only have to take a slice off one axle only. Check it out first. It will work fine.
FYI
Steve