Will 8-3/4 alxes fit in the old 65 7-1/4 rear?

Im in the process of upgrading my rear end. I have the weakling oringinal rear end in my 65 barracuda with the 4 inch bolt pattern. I do however have a set of axles with a 4-1/2 inch bolt pattern from an 8-3/4 rear end. Will these axles work or will I have to put the an 8-3/4 rear end housing and gears...the whole tomato?