Question on oil singers

I have 1975 New Yorker with 440 engine. I took the timing chain cover off and found no oil slinger. I changed the timing chain and plan on putting in an oil slinger . My question; did Chrysler stop putting oil slingers in when they started using a cast crank or does anyone have evidence of oil slingers being used with a cast crank? I saw an oil slinger used with a forged crank on Nick's Garage on You Tube. Paul
Author: spstan