Front-End Loader JD401b interchage with 401c?

[flatheadvff]

I have a friend who found a good John Deere 401b tractor he is interested in buying. He wants a front end loader on the tractor and has also found a 401c tractor with loader. The 401c is an inorperable tractor but the loader is good.I believe the loader will interchange as I think the 401c is just a later model tractor but basically the same. I'm not sure why he asked me. I grew up in my dad's parts store, machine shop, and farming mom's farm, but contrary to what I tell everyone, I don't know everything and ocassionally do make a mistake. If someone can answer this question, I can keep my reputation intact.