I have a sketch of how mine is hooked up, but I don't see how to attach it, so I will send it to you separately. It is, generally as follows:
K3s-RJ-45 from Elecraft CBLP3Y
P3-XCVR DB-9(M) : DB-9(F) from CBLP3Y
P3-PC DB-9(F): DB-9(M) from SteppIR Y-Cable
SDA100-Data in/Radio DB-9(M): DB-9(F) from SteppIR Y-Cable
Elecraft CBLP3Y-DB-9(M): DB-9(F) from SteppIR Y-Cable
I have to have software (DXLab, N1MM, etc.) running in order for the SDA100 Autotrack to work. In DXLab Commander, I have the "Interrogation" box clicked and a 250 ms scan interval & a "1" in the Scan Dwell box. I don't know that these settings matter, but it works well.
Rob - AE7AP