72 Z Master Cylinder quandary

Redoing my brake system for the first time. Got a rebuilt Master cylinder from Black Dragon & found that it:

1) had a two hole flange mount vs the original which had 4 holes

2) the collar which fits in the booster hole is ~1" deep vs 1/2" for the original, thus

3) Master Cyl will not bolt flush to the booster.

4) Dragon says that they have not had any customer issues with fit but are happy to take it back

Has anyone else observed this and do I have any options besides rebuilding or mounting the new MC w/o any spacer?

And what about the 4 vs 2 hole mounting flange?

Have had this Z since new.