Dave,
I have also only seen Z car swaps and all those were for the 2014 and earlier 8.8 diff. There are 2 different designs of this diff, most have one forward mount. The kits are designed around the harder to find 2 forward mount diff. The 2015 and newer 8.8 has a different case design that is available in cast iron or aluminum.
I would think the R200 long nose would be the diff to use in a 510. A Z31 300ZX Turbo LSD unit would be the ideal one. These are extremely hard to find, but you can buy an LSD unit for the R200 short nose diffs (S13/14/15) and it will fit the long nose case. You will need bore spacers for the ring gear bolts, as the short nose diff uses a larger diameter ring gear bolt than the long nose ring gear you will be using.
The 8.8 is 224 mm, so the R200 wouldn't seem to be much of a disadvantage in strength.
Dave Patten, Owner
FutoFab, LLC
199 Stark Hwy So
Dunbarton, NH 03046-4411
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