Hey Jazzyvee,
I believe the only differences is the body shape/size and scale length. For the Signature Deluxe, the Stanley Clark comes standard w/ Rosewood top laminates, while the Mark King comes standard w/ Coco Bolo top laminates.
The electronics are identical, the body woods are the same, and even the wood and laminates used in the neck are identical. Of course, you can customize and change all that.
Mikey/