thats a lot of hide. i would think you could stake them out and dry them in the sun, as long as you could keep the dogs away. would probably kill your grass beneath them by the time they had dried.
i used to tan my deer hides like you are thinking, and after i got them dried and stripped down, i soaked them in a luke warm tea made from brains and oak chips. the oak was for color only. after the skins were removed from the tea they had to be keep moving until they were dried. that is going to be alot of work with your buffalo hides. maybe a trip to the laundro mat with a bunch of coins. good luck.