Ah, it's a Black 'n' Gold! :) I think you're right then, apparently they did have alder bodies, although the catalogues can be a bit confusing! It seems odd that they would be different from the regular CS400 models, but I think they came along a bit later if I remember right, so maybe they just decided to change the specification.
I've never had the chance to play any of the Cardinal/CS models, but I've always remembered them fondly because they were advertised in the very first guitar magazines I bought back in the early '80s, along with things like the Ibanez Artist and Washburn Wing series. I don't know if I'd actually like them in reality, I suspect I'd find the bodies too heavy and the necks too skinny....
If it is alder I'd expect it to be more middy than ash, a bit less bass and treble. I can't really help much on pickup suggestions, but for mostly clean sounds I think you are certainly better off with the more vintage models.