To More4dan and all who have offered suggestions, Thank You! I took the tool to our local Menards today and did a thread test to determine the fastener size needed. And yes, I was looking for the flat head socket cap screw that holds the carbide down. I found it to be (at least on my tool) a 10-24 x 1/2" long. To make the tool more comfortable (for me), I also bought a Forstner bit extender and inserted it between the tool and the handle to increase the OAL of the tool to about 21 inches (closer to that of the EWT Mid sized tools and the one's that I have made myself). It fits nice and snug and seems to work very well.
Thanks again to everyone - problem solved - Regards, Dave (egnald)