Exhaust manifolds

[Jambone <jambone6@yahoo.com>]

Listers,

I have 2 exhaust manifolds (1 loose and 1 on my car) that look very
similar, but they have different numbers on them.  I'm hoping that
someone out there can tell me what the numbers mean and what the
differences between the two manifolds are (I don't have a manual with
this info).

The loose one has "v3069" and "077" stamped on it, and the one on my
car has "3v3069" and "075" stamped on it.  They are both Leyland parts.

My car is a largely original '76 1500 Federal model.

TIA,
Brian Hill