[cfm]

I believe the Canfield head requires a 3/4" reach gasket seat plug. Those plugs are .460 reach tapered seat.

You are correct.

Canfield suggests a baseline plug is the Autolite 3924's.

BKR6E or BKR7E's (NGK V Power) should work out fine. 7's are colder than 6's.

FYI: You must read'm to know what heat range to ultimately use.

Gap to .040" and run'm.