1) If you look at your high speed needle valve, you will notice that it has a threaded hole on the side of it. The set screw goes in that hole to secure an extension wire.

2) I usually run the engine sloppery rich below 4K rpm on the bench for a couple of tanks by opening up both needle valves until there is a huge cloud of smoke emitted from the exhaust. I then break the engine in some more in the air, running it around 700 rpm below peak.

3) Of course, there will be performance loss when you run lower nitro fuel. The 63 runs at pretty high rpm, so 18% oil will provide less protection. YS engines perform best when run on YS 20/20.

4) Fuel line clips are not necessary. I never had a fuel line popping loose yet.

5) This depends on the temperature, humidity, elevation, fuel used, and engine orientation. I think mine is at 1.25 turns out with the engine mounted inverted.