Go to Ebay and type in gleaner. It may take a while but somebody will list some for sale. A 1977 F2 is more like a 1976 F than a 1978 or newer F2. Agco might still have them.
Manuals are available from AGCO.My dealer was ordering parts book for me but said it was over $100.00.Did not get it. May have been money well spent but more than I wanted to spend at this time.He may have told me wrong too. It would not be the first time.
I have 2 parts manuals for an F2 that were picked up at a dealer auction a couple of years ago, I only need one and could sell you the other one if interested. It is slightly used but all there, I think. Neither one covers the heads, just the combine itself. let me know. John
I own a 1976 model m machine and the dealers price is high. I only bought a parts manual from them, still looking for a shop manual. Go to ebay and keep a eye out it will save you alot of $$ good luck Bill