dont mean to make this sound ridiculous but did you put the seal in the right way??? if you put it in the same way you pulled it out doesnt mean it was the right way to begin with. Open end towards the engine closed end outwards.

 

that is true, good catch...

 

A little trick I figured out completely by accident when replacing the seal on my 83:

early and late model oil seals are slightly different, and end up sitting on slightly different spots on the crank. If the crank has a groove worn in it, swap the oil seal with one from a different generation so that it will sit somewhere else.

To this date, my 83 with an oil seal from an 85+ does not leak a drop of oil.