I made a research at ebay and there is a lot of late (black) headlight cases with no number and some with the "1" (black), the "1" type maybe from CB 450-500-550. It is difficult to declare that "1" has small hole and "2" and "no number" are big hole without measure. Someone could measure the hole sizes.
as i said in earlier post, black bucket on usa models began in 1972, K2 models, so to my way of thinking no K1, no K0 and no sandcast would ever have used this black bucket. the black bucket is not correct for any usa models until 1972 K2.
to my way of thinking the blue-green and red buckets are the focal point of interest, as those are the only "sandcast' colors.
Black buckets are different (bigger hole for wire harness) from red and blue-green buckets and black buckets could have there own dies and very probably there own "die numbering," therefore totally separate from the earlier blue-green and red buckets. b-g and red may have been available on later 450 models, though.....
i don't know anything about 450's. but i'm pretty certain there were no candy blue-green 450's in 1969 and possibly no candy red ones either.