300zx diff also requries different axles.
i have a 91+ parts car in St. catharines with a VLSD in it… normally they go for a couple hundred bucks, more in the US becuase they are rarer.
if you feel like getting under it (it’s outside) and removing the diff you can have it for $75.
also… 'Posi" is an American Manufacturers branding term, like Hemi… it doesnt mean anything. The term used by non-americans is limited slip differential… gawd, i hate it when guys convert over to jap scrap and talk about posi trac…lol…