PDF of 1976 USA 308 GTB Owner's Manual - needed

Haven't seen one of those myself (so would be glad to get a copy, too), but here is the 1976 Australian 308GTB OM (and the AUS cars are very similar emission-wise to the US cars):

https://www.dropbox.com/s/edn0gcogvmucy4i/MUM_308Gtb 134_76 1976 Aus version.pdf?dl=0

and the 1977 US 308GTB OM Addendum (1977 US are much more similar to 1976 US than a 1978 US):

https://www.dropbox.com/s/bp5gpggs2d4z5il/MUM_308Gtbna 77 addendum.pdf?dl=0

The 308GT4 WSM would also be a reference for 1976-1977 US 308B/S emission-wise. Does your friend's 1976 US 308GTB have the mounting provisions (and pulleys) for the dual air injection air pumps?

 

There is a 1976 USA OM:
127/76
308 GTB 1976 US owner’s
Image Unavailable, Please Login
I don't have a hard copy nor a PDF, but some originals are available on eBay for ~200. Search for Ferrari 127/76. They aren't going to get cheaper, so I suggest that your friend get one now. Way back when Ferrari had the owner's manuals online (~2001), I captured all that were available, but this was not one of them.

 

is this enough?

ciao