In Reply to: Spark Plug Conduits posted by Tim Daley(MI) on August 28, 2017 at 22:19:50:
Tim, it looks like the red one shown is a match to the drawing 8N-12112-A. The overall length from the centerline of the 4.5" leg to the end of the long straight section is 16 1/16". It was drawn in May of 1947 and the -A was added in May of 1949. That is the only one I have.