(1) The needle seat uses a gasket

(2) The correct needle and seat from the bottom should be: gasket, seat, needle, spring, "golf tee".

(3) Question too general on extra parts to answer, but there is no external seal on the throttle shaft.

(4) USE THE GASKET SPECIFIED FOR THE CARTER CARBURETOR, FORGET ABOUT HOLES IN THE SPACER, UNLESS YOU ARE USING A SANDWICH GOVERNOR.

EDIT: The holes in the spacer are for use with the original Rochester carburetor; the Carter gasket will provide the necessary vacuum signal for the Carter carburetor. If using a sandwich governor, you will need to determine what vacuum signal is required by the governor, and then when to obtain it.

Jon

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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