The chock pull-off comes of just below the one on the top corner about a 1/2 inch and it is angled toword the vacume pot. It was connected when I got it back from being rebuilt. The carb guy said the top corner was for the vacume advance. It has a tube coming from the distributor and when it gets to the front of the carb it curves up and connects with a piece of hose about 3 inches long. I've read about wanting manifold vacume for your advance and wondered if this was or not.

Yes it is an automatic, I did notice on Q-jet numbers the last # is even or odd for auto or 4speed. It does have the correct # for auto. My modulator vac comes off a tee on the manifold between the distributor and the carb. Passenger side to modulator and driver side to vacume canister and accessories.

Does your carb should look like (similar) this? KOPBET2008-05-22 19:09:09

Mine has a straight tube coming out above the one for the choke pull-off. other than that it looks the same.

Can you post the numbers on the carb or pics?

I'm not good with pics but the # is 7042208. according to my ID info is as follows,

Here is a good carb info site http://www.carburetion.com Yet another info site

Your Carb number  goes to 1972 GM truck G10/20 and 30 series 350 all trans if the site number check is correct

That's what I was afraid of. That is not your original carb. If you had an original carb before you took it to the shop it appears they pulled a fast one on you. KOPBET2008-05-24 10:34:28

my AIM book shows this carb for the LS5 big block with the advance coming off just like it is. But now I'm wondering if it has the wrong metering rods and stuff in it. I guess I'll do some inquiring next week with the local carb guys. I looked at the site rraider1 had and he's correct. Since it showes truck 350 it may be the same carb just metered differantly. First I'll chew out the guy that rebuilt it for not telling me.