Not so, at least not all 25 year olds leak oil. I'd place my grandmother's quilt under either my 78 of 67 vette overnight without concern.

After reading all of the above, I now realize how lucky I am - (and I thought I was just good. What a disappointment!)

One thing that I have done (left over from my blueprinting days) is to dynamically balance everything that rotates when the engine is apart. Those subtle vibrations at high RPM often seem to cancel each other out somewhat when running at low RPM and bolted together but they can accelerate wear on bearings and seals. But I'm sure that is NOT causing the problems listed here.

I suggest trying a different brand seal next time in addition to the other excellent suggestions above - that has made a difference for me in the past on other applications.

David