nanual of na 20 (s)

Friend there is no problem with the model and the engine, I have a Nissa D21 with a na20 carburated engine, the vehicle is 100% Japanese, other D21 models have diesel engine or gasoline of injection, the manual for that engine is very difficult to find it I have searched for it for everything Internet and nothing, to the engine is very scarce, only in the nissan concessionaire I have seen spare parts. But if I get something I warn of

greetings