Seymour Cray had more than a hand in the design of the
6000 series.
Although he worked with some fine engineers (Thornton (sp?) is one name I
remember), I believe that the instruction set, architecture and packaging
scheme all primarily came from Seymour.
Apparently Seymour did some of the bits of the 6600, like the I/O.
The scoreboard and other innovations were Thornton's. Somewhere
there is a thread about that on comp.sys.super, but I can not find it now.
William Donzelli
william(a)ans.net