Typically on some warbirds engine are mounted at 135 degrees to center the muffler under the center of the fuselage and of course ninety degrees works fine on many airplanes and is my favored mounting orientations.

Both work well and neither have as severe fuel tank/spraybar relationship problems or the syphoning problems of an inverted setup.

However the way it is done is to put the throttle pushrod where it needs to be and in the vast majority of installation is along the bottom right side of the nose section. If you are going to change the engine orientation then that is where you position the pushrod.

You never said what the engine is and now on some it will not work. For example if it is a LA series engine then that bleeder hole needs to be facing forward directly into the propwash.

The thottle postion on any engine dictates where you put the pushrod not the other way around.

John