This is probably a rare item. A feller here has a '99 LS. It is a Gen 2 in every way except it has the SOHC 3.5.
I'll bet it's a cheaper and a little simpler engine to maintain.
He won't sell it.
There's still a 4.36 SR locker in the yard here, 135 K , 1996. San Luis Auto . They'll ship.

dave h.
'89 Raider V6 5spd;Aisin Hubs;; Gen2 LS: frt. brakes, rear coils;U.C.arms;R.trailing arms;idler arm; rear LSD axle w.disc brakes ;2 battery system for Dog's fan; relocated ECU; custom bumpers;J.Baker receiver;Conferr roofrack; t-bar crank.