I would never rely on a Haynes or similar. Too much 'generic' info combined from different models.
Get a specific FSM.
I recall a kit but it requires reamers and so on, IIRC.
Disregarding the idle screw for a moment, your symptoms may be related to wear around the throttle shaft - if so it would benefit from re-bushing....
Yes. My opinion is that "tuning" an F-head is a misunderstanding of the 4-cylinder Jeep heritage.
If you need more power, look for a V6 jeep.
One source I read claims that double flare will hold higher pressures than bubble type.
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