How many degrees to the right, should the engine be mounted, to counter the thrust given by the engine?

• Great Planes (2-piece) engine mount
• OS .46FX
• Hobbico Avistar Mk II (40)

I've mounted the engine once already, but decided to buy a second mount and remount the engine correctly, using the "thrust correcting angle", in my first trainer airplane.

The engine will be mounted flat onto the mount(s), but I want to turn it toward the right... by what... 2°, 3°, 4°, 5°... or what?

Also, the engine-mounting screws that came with the ARF, are #6 phillips head...
I have decided to use "Du-Bro" #6 socket head (allen-head type) screws instead...
Am I suppose to use washers? I bought some lock-washers, but I've not seen ANY information regarding their use (engine-to-mount).
I am using those star-type washers for the mount-to-firewall.

I want to get this finished so I can begin to break-in the new engine so I can fly my "maiden voyage" on Thursday afternoon

Thank you.

"MacAir"