I got the quote from Precision a few days back, and I have been mulling it over. To pour a 5x6' surface plate + self-leveled rails would be 10.5 gallons @ $89, and cost $952 + shipping. That isn't going to happen. The reason it is so expensive is that they think I would need to do two pours at 1/4" each. I'm Scrapping that idea now that I know what it costs! I next thought I would just pour a plate small enough to pour the concrete bed on - let's say 38x50". That gets it a lot cheaper. Then I started reading about how concrete continues to shrink for years. (nuts) So I would have to be somehow re-milling/grinding/sealing the top surface every so often. I don't know if that's even possible. It made me stop and think that drilling holes in granite is not so bad! I am going to go visit some granite places and see what I can find. I'm thinking 36x48x4". Maybe they can drill the holes also!

FYI, here is what Precision Epoxy would supply:
7.0 gal. SC-15P A Steel casting epoxy @ $89.
3.5 gal. SC-15P B Steel casting epoxy (part B) @ $89
1 5" mixing blade @ $15
1 10" wood handle spatula @ $2.40
All of this comes in pre-measured kits for each pour. The part A is in a container big enough to also hold part B. Just pour in part B, mix, and pour.
They also said I could call any time day or night for tech support (you can see they are geared up for big jobs).

The odd thing about this is epoxy is that their web site says SC-15P has "a reduced pot life and rapid rate of cure". Exactly opposite of what I think I need.
Here is the full description:
SC-15 (mix ratio 2:1 / A:B)
Steel Coat Epoxy was formulated to protect steel plates subjected to submersion in boiling water from corrosion. It offers unparalleled adhesion at high temperatures without delamination. SC-15 is very durable and chemically resistant with a reduced pot life and rapid rate of cure. Available in clear or pigmented, thin or thick viscosity liquid, paste or gel versions.
I just sent them an email asking for clarification.

I am going to move forward with other parts of the build. I have a surplus metal supplier in the area. I'm going to head down there soon and see what they have.