so if i buy a vlsd, from a 92 that had a sr20, will it fit into my 89 with a ka24e?
yes, it will fit.
Any r200 Diff will fit. you will need the vlsd output shafts as well. if you just have the diff itself, and use your open diff output shafts the vlsd will act like and open diff. one of the vlsd output shafts is longer than the other, make sure to use them and install them on the correct side.
isn’t one of the shafts already longer then the other? on a reg dif?
no, on an open diff they are very close if not exact, and will not work in a vlsd or better lsd