[Gromit]

A couple seals I would check would the one on the dipstick and the one on the oil filter adaptor; both should be cheap (though the oil filter adaptor one seems hard to find; maybe the dipstick one too, since I just bought a new dipstick instead of hunting for the seal).. photos attached..

I never did find a torque for the oil filter adaptor bolts; so I just used a standard torque chart for that size and thread pitch..

These two seals or gaskets are often overlooked.

That is the Allstar performance version of the oil filter adaptor in the photo - 1/3 the price of the GM one.

I don't know anything about the 327 except that it is very similar to my 350 so I hope this still makes sense.