Finished getting the engine mounted on the plane and everything hooked up. Started the engine. Ran great. Adjustsd the idle. Oil pressure didn't seem right .. so I hooked up a mechanical guage in the front port and restarted. Mechanical read normal readings. I recall on my previous Sonex .. the oil pressure was reading high. On that one I replaced the sendor with the GRT recommended VDO 360-004 and it was fine. I ordered one of those to try for this engine. After a few starts I noticed an oil leak at the back of the engine. Back off the plane it came. i put it on the bench and removed the flywheel. I noticed all the oil was on the outside of the flywheel in the alternator area. None on the side by the engine. Apparently i needed to put more red RTV between the rear crank hub and the flywheel than the "light coat" called out in the engine manual. I had Advance Auto order me a couple new rear seals for in the morning. At least it wasn't the cam plug where I'd have to split the case.