Quadrajet gaskets

[drmiller1]

Hey There,
I have a 1969 350 with the stock quadrajet on it. I had this carb rebuilt. When I pulled it off, there were 2 gaskets that sandwiched one very thin metal spacer. The spacer cover the "shallow trough" in the front of the intake where the carb bolts on. I mentioned this to the rebuilder and he said to just put a single gasket back on, this leaves the "trough" open.
Now my engine will start and run, but idling is a problem. Should I put the metal spacer back in? Any ideas? thanks.
note:adjusting the idle screws does not seem to make much of a difference other than seated all the way in. This causes a stall.