What is the proper way to locate the engine/mount on a plane that has a firewall or an engine box with built in right and down thrust angle? I am attaching some generic photos - I do not have this plane but I think the photos are good reference.
How do I use the marked x-hairs? Why are there two vertical lines? Should I locate the center of the thrust washer aligned with the center line or should I reference some other location on the engine?
Second, how important is it to locate the engine vertically? I got a 46 size edge 540 and I would like to mount OS61. The engine and engine mount are laid sideways with the upper mount butted against the top of the engine box. If I try to mount the larger engine I need to relocate the lower half of engine mount down to make room for larger case. That puts the CL of engine approximately 4mm lower. Other than mismatched cowl, what else may be affected?