Oh boy... I shouldn't get involved in these threads, like trying to chase down electrical problems from a thousand internet miles away. LOL.
First off who makes this "new kit"?
Second, what did you use to clean the carb body & parts?
A Gallon pail of carburetor cleaner which in the old days is just basically 'Lye' or rattle cans of carb spray?
I wonder if you can still get the 'Lye' type soak stuff anymore.
Third, is how is the throttle shaft play?
Tight or loose?
A good thing is the screw head slots and phillips don't appear to be too buggered up much so this carb may not have been apart too many times (less hands on, less flucked up) which is good.
The reason I ask is I still see crude (brown staining) in the bottom of the bowls and some white crap on the brass tubes. While this don't seem much to the naked eye with time can dissolve/break off/float away and end up in your check valves and jets.
The interior of the carb should be pristine shiny clean, the aluminium should be free of any stains and I see some corrosion in areas which is not uncommon but should be scrapped clean or bead blasted glass/walnut your choice but never use sand on aluminium.
Red arrows to corrosion, green circles stain/crud that can be cleaned with a small wire brush. The metal baffles can be removed. If you got staining and corrosion in these areas what do the narrow passages & tubes look like?
Little **** can creep out of corrosion over time and get into places you don't want it.
Check you accelerator pump bores for any corrosion and don't trust your naked eye, get a strong lighted magnifying glass and lightly smooth them by scraping or emery paper.
If there are serious pits of corrosion in the accelerator bores the carb is must likely junk unless you have access to the ability to hone it or sleeve it.
Make sure you got the right kit as in your picture is this the right bowl cover gasket?
Or is it the picture/angle not right (maybe a air gap here).
In searching around the net for some good Carter documentation I found what this guy says are 1968-71 CARTER AVS 4-Barrel Carburetor NEEDLES & SEATS wGaskets N.O.S (eBay Carter Carter Part No. 42)
Now here's a clean carb (NOS).
Sorry to rain on your parade but back in the day I had many customers seeking me out to rebuild their carburetors. Never had a come-back either.
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