Homer, If you grab those, you better start coming around the Polk forum and posting. Its mandatory for all Polk SDA owners to come there and hang out in the
vintage speaker section!
Seriously though, There is a wealth of SDA knowledge there, including schematics, wiring diagrams, upgrade talk, etc.
I just finished all the upgrades to my SDA-1C and they are just amazing!
Hope they turn out to be in good shape.