The carburetor on my 1984 El Camino (229 V-6) is a Rochester Dualjet. There is a number stamped on it: 1707300. I have the 1984 Shop Manual, and it identifies (on p. 6C2-31) only 2 Dualjets (and their settings) for the 229 V-6: #17082130 and 17082132.
Does this mean my vehicle doesn't have the original carb??

This is the only other Dualjet thread I could find: http://elcaminocentral.com/modules.php?name=Forums&file=viewtopic&t=3106

The third and fourth numbers on the carb reflect the application year. The numbers you list (17082130 and 17082132) are for 1982 229 V6 applications. The 84 shop manual is lying to you. The 17082130 is without AC and 17082132 is with AC.

In 1984, any G-body or B-body with a 229 V6 should have come with a 17084132 carb. Check the number on your carb again because it seems to be missing a digit (1707300?).

If I can get my hands on a digital camera I'll post a picture. Until then you have me wondering if my eyes are deceiving me.

I checked again and found I left off the last zero. -> 17073000

I checked again and found I left off the last zero. -> 17073000

That number is a casting number of the carb's body itself, which might also be used on many different Dualjets for many other applications. The actual Rochester carb number is located on the driver's side of the carb, BEHIND the left barrel, on a vertical rib running from the base to the air horn, right above the left-rear carb mounting bolt. You likely cannot see or read it without removing the carb from the engine, even with a mirror.

And yes indeed, Virginia: the correct carbs for the '82-'84 229 V6 engines ARE the 17082130 and 17082132. GM used older carbs on some applications, not necessarily updating the carb PN if there was no actual update to the carb itself. I have a 17082132 from my original '83 Malibu wagon with 229 V6 with AC, and a 17082130 from my '84 Elky with 229 V6 without AC. Both carbs outwardly appear identical; I strongly suspect the only difference is in the Idle Speed Control motor. I doubt there were any later-stamped carbs than these since '84 was the last year of the 229 V6.

Thanks Steve. That was a very helpful explanation.

Glad it helped! I've got a web page where I've listed all the carbs used on various Olds engines from 1982 through 1990, where you can see that Rochester didn't update the carb number for some of the carbs:
http://members.dandy.net/~k0xp/Oldsmobile/E-Qjet-Parts-PNs2.htm

Rochester carb numbers for 1976-1980 carbs generally seem to begin with 1705xxxx, with the specific model/application of the carb being indicated by the last three-digit numbers in place of the xxx. It's been said elsewhere that an odd or even number in the sixth (if I recall correctly) digit's place indicates whether the carb was used on a manual or automatic tranny. And indeed, that may be the case for EARLIER carbs but it certainly doesn't hold true after 1976. In 1981, Rochester carb numbers began with 1708xxxx. Prior to 1976 I believe, the carb PNs were only seven digits, beginning with 70xxxxx. The last three digits were assigned depending upon the carb application. Carbs with very similar applications or calibrations seem to have received numbers very close to one another.

So the year that the carb was first used is indicated by that fifth digit in the case of an 8-digit PN, or the fourth digit in the case of the seven-digit PNs used for earlier carbs. So in your case, your 17082132 or 17082130 would be read as the carb first being used in 1982. As Ernie said, you might have expected a 1984 engine to use a carb with a number such as 17084132 but evidently, they did not change the carb's calibration after 1982 and so it retained the same part number through the last of the 229s in 1984.

What's interesting about these two carb numbers is that it indicates that 229 V6 engines were not changed from 1982 through 1984. Besides indicating that you can swap parts among those years, it also indicates that the same ECM can be swapped among those years with the following limitation: you need to keep in mind whether the engine had AC or not. While you can probably use an AC ECM on a non-AC-equipped 229, the AC may not operate properly if you were to try using an ECM from an Elky without AC, because the AC-ECM used input signals from the AC pressure switch to raise the idle slightly to compensate for the extra load.