Questions about 1675 date wheel

[finance21]

I know this was previously posted but I was unable to find anything with my search criteria.

What serial range did the 1675 use silver date wheels (if any)?

What serial range can you expect to find open 6 and 9?

Should the 6, 9, 16, 19, 26, 29 all be open?

Which serial range should be hacking?

Thanks in advance!