Is it possible to use the YV-666 Bosk ship for 35 and then add the Bosk Crew Card ? Just wondering what the rule is in this situation. Thanks.

Any card a dot next to its name is a unique card. A squad can only have one unique card with the same name. It doesn't matter if they are different card types.

As noted in the Rules Reference Guide, on Page 19:

UNIQUE NAMES
Some Ship cards and Upgrade cards have unique
names, which are identified by the bullet (•) to the
left of the name. A player cannot field two or more
cards that share the same unique name, even if
those cards are of different types.

So the short answer would be: "no"

That wasn't an overly long question though, so it doesn't really qualify for a Short Answer to a Long Question^TM

Which is precisely why I didn't refer to it as "a Short Answer to a Long Question^TM"

Thanks for all your responses...much appreciated.