I finally found a bone yard in Texas that had a combination proportioning valve from a 2003 S-10 with relative low mileage(117k). I replaced the Master Cylinder and the proportioning valve. I am back to normal. I believe that the master cylinder was leaking internally and the proportioning valve was leaking out of the rear port.
I took apart the proportioning valve and only a single o-ring. The other portions are rubber discs. I need to see if anyone has the replacement discs to rebuild the valve and just put on the shelf for later.
Thanks for the insight.
2012 Best of ISSCA; 2013 ISSCA Nats FTD Autocross and Road Racing
1995 BBB: - ERE383 #74 516 FWHP/526 FWTQ
1984 Monte Carlo SS 12.8 @ 104
2005 GTO M6 357.7 RWHP and 358.8 RWTQ PCMFORLESS