do you have 4 into 2, or 4 into 1 exhaust?
Yes, low 30's mileage is poor, and you should easily run faster than 60.
Step 1. pull and clean your carbs. ensure the float valve, idle and main jets are clean and clear. set your float heights to 22-24mm.
I had no experience with carbs before my 350F. you wont get in over your head. trust me.
you dont need to separate the bank of carbs, just remove the bowls, and carefully lay each piece out on a towel after you clean them with carb cleaner. do one at a time.
and you really should bench sync your slides while you have the carbs off. get them all close.
Step 2. as mentioned above, do a full tune up.
Points/condensers/timing/valve adjust/oil and filter/air filter, and vac sync your carbs.
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