1974 450SE oil leak

[witty]

Hi folks

Would appreciate some input, my car has been sitting for about 3 months and no problems, did the timing yesterday and all was good.

Today however I went to the car only to find a trail of engine oil had leaked onto the paving and run about 10 feet down the length of the car.

After inspection I believe it is coming from around the rear seal area and dripping from the bell housing.

My car is parked on a slight slope, but I dont think that would have any effect on the issue.

Do these things just happen overnight ? or are the gremlins active.

Is this a common problem?