RE: HOW-Where to drill to mount engine
I personally would not use the hole in the firewall as a reference. Follow the centerline possibly shown in the instructions. It should not matter what engine is installed. The alignment of the engine shaft to the centerline of the airframe remained the same. Shift the engine on the firewall to meet the same centerline as shown in the instruction or if necessary use the cowl to find the center and the align the engine shaft to that center.
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