Is this a B body k frame?

[Rainy day auto]

So if this were an A body, I'd know exactly what it is but I'm not really familiar with B body k frames.

So I'm asking the b body crowd, are the holes in the bottom supposed to be there? And does this look like a b body k frame?

I am intending to use this in a 67 belvedere 1, to v8 swap it. It currently has the original slanted k frame.

I also posted this query on FABO but no one there seems to know for sure, so any insight is appreciated.

 

[Kern Dog]

Yes. The curve at the front is the clue. Most A body K members are somewhat straight across along the middle, B body units have a gentle curve:

This is a 440-6 K member from a 70 and later B body.

Here is a 73-76 A body K member.

Make note of the straight front edge.