Can you help me with a Yamaha precision blend outboard.?

[Canobeer6]

I just acquired a 40hp Yamaha model ELRR and need some info. This unit has an oil tank under the hood which made me think motor is a 4 stroke, I was always under the assumption if you mix gas/oil in the tank motor is 2 stroke, and if it mixed itself unit would be a four stroke. When I search for info the unit comes up as a two stroke. Anyway I have a couple basic questions. 1. Do i just put the oil in the reservoir under the hood or do I indeed have to mix it with fuel. 2. Recommended oil? 3. Motor doesn't have harness/controls the plug on the outboard looks to be 10 pin. Can anybody tell me what harness/controls to order. Any other help appreciated. This thing a little more advanced than my 70s Johnson