Hum... I think that a combination of a silicone sealer, along with an o-ring would be best. Industrially, they use huge mounting flanges to connect pipes, that seem way oversized.
Calculating the structural load is out of my league. I give up! I'll have to take my chances with a thick piece of acrylic/perspex/whatever-other-names-are-out-there clear material.
In my search though, I found an interesting link:
http://www.engr.usask.ca/~drs694/fluidmechanics.htm
Utabintarbo: I think I like your idea best. I just wish I knew more about those 4 pads on the Athlons. Are they just common rubber?
As per AMD specs, the core is between 0.80 and 0.88 mm high, off the face of the processor (so that's why we don't use a shim!). The pads are max 1.90 mm thick, so I have to assume that they have a certain "sponginess".
Otherwise, the whole processor width (it is square) will fall within 49.27 mm and 49.78 mm. The core is either 7.31 by 11.06 (for Model 8 with CPUID of 681) or 7.47 by 11.33 mm (for Model 8 with CPUID of 680). Now which is Thoroughbred rev B?
I'll be back with socket specs.