GTV 2000 carb Q's

[Jeff Matson <jsm8@domain.elided>]

OK, bet you've never heard this one before:
I've got a '74 GTV 2000, long ago converted to Weber DCOE's (early 80's
based on records I have).  The puzzler is that the records I have
mention that the car has a 1600 intake manifold.  I can't figure out
why, other than maybe that's all they could find at the time.  There are
also a bunch of other receipts for tuning (jet changes, etc) indicating
it took a while to get this setup to work well.  (It runs great now, but
I've never driven another GTV to compare "spirited" response.)  My
questions are:
1.  Can this really be true?  1600 intake m'fold on a 2000?
2.  Would it be worth my trouble to try and locate a 2000 intake
manifold and make the switch?  I assume I'd have to then change most all
of the jets and such in the Webers.  Any thoughts on where to look for
such a part?  How could I identify what m'fold is on the car now?
3.  I can't sort out with much certainty what's in the carbs now. 
Original setup had 30mm venturi, 50F8 idle jet, 135 main jet.  I believe
it now runs a 125 main jet (last records show this change).  I do have
notes from the P.O. showing some chats with Weber people, but I don't
know if he ever had anything done or not.  Can anyone comment on whether
these make any sense?
4.  Am I better off keeping my fingers the hell away from the Webers and
just driving the car?  That's sort of my inclination right now, but if I
could get a decent performance improvement by getting the correct 2000
intake stuff fitted I might make a good project out of it.  I'm good
with this sort of stuff, just never touched carbs before.
Any tips/input are greatly appreciated.

Jeff Matson
Harvard, MA
'74 GTV 2000
'91 164L

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