I had just been notified that I had the ID's of the bridges mixed up!...I would like to thank Mike and Peter Kavcic for catching this mistake..The Info below has been corrected.
1978-1983 350 Diesels, had Rocker Arm Bridge pivots that would wear prematurly..thus causing a ticking noise and/or a Back Fire condition...These Bridges are Identified by the Y Underneath in the center..The new ones have a Diamond instead of a Y. This condition usually does not affect smooth operation. If you are experiencing this condition, and your engine is 1983 or before..check the rockers. Remember to replace ALL and not just one.
For Performance Upgrades available for Rocker Arms, see Roller Rockers in the Performance Upgrades section.