P01S0N312

I have been looking for the past 2 weeks for a differential for my 87 nt, i have come across some pages and charts saying a Miata diff with fit, which is fine and dandy but i lack the current funds to buy the l/s diff i want, i happen to come across an 96 Miata open diff and was wondering if it will fit on my rx7. i don't need the limited slip diff just something to get me by for the time being. Can anyone please tell me if a 96 open diff will fit my 87 rx7 or not before i waste my money and find out the hard way please and thank you.