Try to get 0 play on the cam
Roller cams screw in n out of their bores: distributor gear wear is your 1st hint n choose the right distributor gear for cast or billet cams. Cam degreed with lifter or with head n on spring retainer ?
Cam C/L ? Automatic or Stick ? no bushing on crank:I assume automatic
454-Littlefield 8-71- two 850s- TH400- DANA 4.33s - 3900lbs 9.74@139mph
https://youtu.be/ICZYERXFyMA