Power steering pump interchangability??

I need a new power steering pump on my 77 because it's been leaking but mine looks like this

His has a bracket that bolts to a bracket that looks just like the bracket that is holding my Power steering pump on. My question is can I replace my pump with the one I take off of his truck? I figure I'll have to get a longer belt but thats no problem. I just didn't know if it would mount up and the fluid flow or what ever would be the same to go with my steering. If anyone has any ideas about it I'd appreciated it, if it won't work then I'll just go get a pump like the one I already have from autozone.


