Dixie Precast Inc. is a company that makes concrete foundations for signals, including crossings. Given awards by Conrail & CSX and very commonly used on the SOU.

I also posted another company related to it in 104, called Sectional Foundations Inc.

1 and 2. Between 1935 to the Early 1960's when the WABCO Style HC-100 replaced it.

3. Still somewhat common if you know where you're looking although their numbers have been declining for decades now. Several crossing installs from the era still have them as US&S used to dominate the crossing ...