The lever you mentioned is supposed to direct the air intake from the exhaust manifold area until the intake air hits a certain temperature - think it's about 80F, and then it will pull air from the forward portion of the air intake. So no problem there.
I would recommend taking the air horn off the top of the carb and checking to see if there are floaties in your fuel bowl. You can remove the two plugs on the front of the carb and drain the fuel out of the bowl. Floaties can get lodged in the jets and stall the engine at idle (or at any other speed, but mine was stalling coming up to a stop and it was because of floaties). Make sure your fuel is clean.
Also, make sure the wire on your carb is connected to a switched 12V power source. I do not see it in your picture; there is a solenoid valve on the rear of your carb, on the corner closest to the block that should have a wire sticking out of it. Needs switched 12V power.
I would recommend taking the air horn off the top of the carb and checking to see if there are floaties in your fuel bowl. You can remove the two plugs on the front of the carb and drain the fuel out of the bowl. Floaties can get lodged in the jets and stall the engine at idle (or at any other speed, but mine was stalling coming up to a stop and it was because of floaties). Make sure your fuel is clean.
Also, make sure the wire on your carb is connected to a switched 12V power source. I do not see it in your picture; there is a solenoid valve on the rear of your carb, on the corner closest to the block that should have a wire sticking out of it. Needs switched 12V power.
