I use 3M on every trouble spot (oil pan corners and intake corners) on every engine I put together and still have yet to have a problem. I have changed many cams without dropping the oil pan, just use some tin shears to cut an angle on the inner lip of the corners of the lip seal, rubber hammer to knock it back in the oil pan and good to go. I'm sure someone here has done it this way also. NOTE: Nowhere in this post did I say it was easy! lol