Spark plug recommendations

1983 318 from a ramcharger.

Stock long block. Stock compression

214/224, .444/.466 cam. 112 LSA, 104 ICL. Hydraulic.

Holley street dominator intake with Holley 390 cfm 4160 carb.

Mopar performance electronic ignition kit with MSD blaster 2 coil.

Currently looking at champion 405's.

No brand loyalty in mind. Just looking for all suggestions as to a starting point with a mild cam 318.

Also, any suggestions on total timing for startup and cam break in are appreciated.

Thanks. Eric