[Jim Sims]

I own a 1976 California spec 911S - very similar to your 1977.
These cars never had a catalytic converter nor an oxygen sensor so leaded fuel will not be an issue for these type of components as you don't have them. However leaded fuel fouls spark plugs more readily and since the car was designed to use unleaded fuel I would recommend you run the highest octane unleaded fuel you can find. The cars did have thermal reactors which tended to cook the bottom of the engines resulting in leaking oil return tubes and very short valve guide life - if your car came from Arizona I suspect the thermal reactors have been removed.

A couple of other suggestions:

Never run the car without the engine cooling fan working; if you lose the fan belt pull over immediately and turn off the engine. An alternator light and the brake light coming on are indications of alternator failure/belt loss.

Do not disconnect the battery with the engine running - this can damage the alternator.

Do not reset (do not push the button) the trip mileage (trip distance) odometer while the car is moving - sometimes this loosens a a small plastic gear on a shaft and the trip odometer will stop working.

Do not speed shift the transmission; shift deliberately with a slight pause as you pass through the gears.