^yay!
A-ron - to answer your question yes. It will fit in your s13. But you will need to use YOUR S13 cover and his s14 subframe bolts. Thats assuming the diff he uses 6 bolt axels. If you guys are swapping diffs he'll need his s14 cover and your s13 bolts for the subframe. Hope everything goes smoothly.
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RIP Tim Aldrich
"..watch this
cool documentary on bums racing shopping carts downhill, and making a living off of selling bottles. living the dream."