Rearend modification costs?

I have the 8.8 but if I had it to do all over again I would have just left the 8 1/4 in it. I don’t race it much just a couple times a year. I have gone from 7 1/4 to 8 1/4 to b body 8 3/4 to 8.8. Got my money back every time but not my time. Do your research stick to your plan Don’t wait to upgrade save and do it all at once.