85 250 big red rear on 4trax 300

Tomorrow I’m going to go buy an old 85 big red 250 in hopes of putting its rear end on my 300. Now I know I will have to either weld a bracket or my 300 swing arm to the axle tube, i know what I have to do to make it fit. I just need to know if this will work, as I have seen a thread on this in the past, but there was never a definite yes that it works, due to something unique about the diff I’m not sure what it said. But will this swap work? Thanks in advance for the help