Heater Levers

I believe the stock set-up on all the carbed 308 is two air distribution levers and one temperature (hot water flow) control lever. If by "heater lever" you mean a temperature control lever, I don't see why you'd ever need more than one since there's only one cable-controlled temperature coolant valve. Since we know that these stock levers break often (and it's been 30 years ) probably a substitution if you've seen something different.

 

There is 1 extra lever in the carb cars and that is for the choke. So it's left defroster , heater valve , right defroster and choke. 4 levers

 

Ditto what Steve says. My car's also a '77 carb.

 

Well, I don't know I would call it the defroster lever. It is marked D E F but the function is more than that and quite sinister. The markings on the right side are 0 up-down and down. It has to be in the 0 position for A/C usage or if just "off". In the up-down position you get heat going up from the dash and down from the below dash vents. In the down only position you only get air from the vents below the dash. But, yes, four levers .

 

Vent lever is a more appropriate term.

See the owner's manual, downloadable from the ferrari owner's site:

www.ferrariowners.com