The O2A vs 04A, and the TU vs SU method of identifying models that had the LSD, is totally false.
In the past month, I have found 6 RX300's with the LSD. All of them had 02A on the sticker, and all of them had SU on the diff cover. This has been in northern California
Pulling the drain plug and using a bore scope is definitely the easy way to confirm without pulling the diff.
And on that note I still have two for sale 😁