Yep, the trans is definitely alder. Very warm and punchy. It has a converted ebony board with lines which matches very well with the whole package.
Not sure about the black - could be poplar, could be ash. But yes, a full sounding 2 band with a great aggressive sound but not ear splitting highs (though that could be the 2 band).
I toured and recorded with a black/maple 1994 back in the day. That had a three band and was a clicky mess a lot of the time. I only ever fully embraced the Stingray again when I picked up a classic with a 2 band and found it much more of an appealing sound for what I like to do.
The necks on those two '89s are slimmer than the 1994; extremely playable, almost jazz like but with a tad more heft. Both pretty light too. I found the '94 neck a completely different ball game. Sharp edges and tubby...was not great!